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美式足球(American Football)  

2010-02-09 08:08:12|  分类: Music&Sport |  标签: |举报 |字号 订阅

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美式足球的比賽實況

美式足球球型像橄欖,在球的一邊有縫線,是用來幫助球員傳球時附加旋轉。

美式足球(American Football),或稱美式橄欖球,是橄欖球的一種衍生運動。有時與加拿大式足球並稱為烤盤足球。 橄欖球傳入美國後,人們把規則改變,包括改為可以向前傳球。由於球賽中往往會與對方球員有身體衝撞,因此球員需穿護具及頭盔出賽。

美式足球是美國流行的競賽運動。這運動的目的是要把球帶到對手的“達陣區”得分,主要用持球或傳球兩種方式。得分方法有多種,包括持球越過底線,傳球給在達陣區內的隊友,或把直放在地上的球踢過兩枝門柱中間,又叫射門。比賽時間完時得分較多的一隊勝出。

美式足球首先由哈佛大學學生以一種名叫“Ballown”的球類運動開始,這個運動的目的是要帶著球跑過對手。在美國內戰結束後美式足球開始在大學中廣泛流行。羅格斯學院普林斯頓大學1869年打了史上第一場大學美式足球賽。這個運動最初跟英式足球相近,耶魯大學教練坎普(Walter Camp)將它改良至比較接近橄欖球。由於比賽身體碰撞劇烈,有報導指球員在比賽中死亡,總統西奧多·羅斯福下令將比賽規則改變才未導致此運動的滅亡。

美式足球與橄欖球的分別在於美式足球用球上有白色縫線,以利於球員抓球及傳球。而橄欖球則較為大顆並且沒有任何縫線。

目录

歷史

美式足球及(英式)足球均從英國在十九世紀中期流行的各種「足球類」運動的玩法中演變而成。其中,美式足球是由英國的橄欖球直接演變過來的。

橄欖球最初由英國陸軍加拿大蒙特利爾麥基爾大學(McGill University)比賽時傳入北美洲加拿大式足球及美式足球就從這裡開始演變過來。

美國的大學帶動美式足球的增長。第一場校際足球賽於1869年11月6日,由新澤西羅格斯大學普林斯頓大學。比賽最後由羅格斯以六比四擊敗普林斯頓,儘管那場由廿五人互相對壘的類似橄欖球比賽跟現代的美式足球沒太多相像的地方。

現代美式足球的型式在1874年哈佛大學蒙特利爾麥基爾大學的三場系列賽中發展起來。麥基爾當時玩橄欖球式足球,而哈佛則採用較近似(英式)足球的「波士頓」式。由於沒有統一的球例,所以兩隊輪流以自己的球例比賽,以示公平。哈佛的球員喜歡橄欖球球例中的帶球跑動,於是於1875年說服耶魯大學以橄欖球球例作為他們兩隊比賽時用的球例。1875年,耶魯、哈佛、普林斯頓及哥倫比亞大學以橄欖球球例組成了「校際足球協會」(Intercollegiate Football Association),但得分球例則稍作改動。

1880年,甘普(Walter Camp) 引進了攻防線來取代橄欖球的並列。1882年,為了制止普林斯頓及耶魯大學用「控球但不嘗試得分」的拖延策略,有限進攻機會的球例被開始應用。1883年,在坎普的建議下,場上球員的數目被減至十一人,同甘普亦規範了七人進攻線、一位四分衛、兩位中衛(halfback)及一位後衛(fullback)的排陣。甘普在1925年4月在前往俄亥俄的坎頓(Canton)出席一個美式足球規則改進會議時不幸遇上車禍去世,他對改進美式足球的規則,以及使美式足球脫離英國欖球色彩等的功勞絕對功不可沒,他被視為美式足球之父(Father of American Football)。

1895年9月3日,在賓夕法尼亞州的 Latrobe 舉行了第一場職業美式足球賽,由 Latrobe YMCA 對 Jeannette Athletic Club 。結果由 Latrobe 以十二比零勝出。

到了十九世紀九十年代,連環進攻陣式(interlocking formation)如 flying wedge 以及隊友把控球的球員強行向前拖動都令到美式足球非常危險。儘管已採取了對 flying wedge 陣式的限制以及推行了其他的預防措施,1905年仍然有18位球員於比賽中受傷死亡。當時的美國總統西奧多·羅斯福向大學表示,比賽一定要變得更安全。為了使大學重視他的憂慮,羅斯福威脅會逼迫國會立法,把美式足球比賽列為聯邦罪行。

1906年,兩個原為對立的組織 Intercollegiate Rules Committee 及 Intercollegiate Athletic Association 在紐約會面,它們最終同意幾項令美式足球更安全的新球例,包括在攻防線之間設置中立區(neutral zone),以及每隊都要有至少六名球員於攻防線列陣。但最重要的改革首推將向前傳球(拋傳)合法化。這球例在當時是極具爭議性的,而且被純粹派們所嘲諷。為了令球員們於比賽時較為分散,坎普提議把球場擴闊;但與會的哈佛大學代表指他們新建成的哈佛球場沒有擴建的空間,因此採用了拋傳提議。這球例亦建立了美式足球跟其他同由橄欖球演變出來的足球類運動的分別之處。

1910年,在更多的死亡個案後,連環進攻陣式被禁止了。1912年,球場的長闊被改至現在的尺寸,達陣的得分增至六分,以及每次進攻加入第四次進攻機會。此時,比賽已改革到現代美式足球的模樣了。

流行程度

美式足球在美國已經超越棒球成為最受喜愛的運動項目。由32支球隊所組成的國家美式足球聯盟是最受歡迎也是美國目前唯一的主要職業美式足球聯盟。其冠軍賽超級盃擁有超過一半美國家庭電視收視率,同時全世界有超過150個國家電視轉播這場比賽。超級盃星期天已經成為年度大戲,其舉辦時間介於一月底二月初之間。該賽事同時也是全美國收視率最高的電視體育節目。

大學足球賽亦十分流行,在沒有擁有美國職業美式足球聯盟球隊的地方尤其叫座。一些大學的球場擁有超過十萬個座位,而且經常售罄所有門票。就算是高中學校的球賽亦常有吸引超過一萬名觀眾入場;當中以美式足球最受歡迎的地方,如德州、俄亥俄州、佛羅里達州、喬治亞州等尤為常見。而在許多美國的小城市,秋季每週所舉辦的的大學與高中美式足球賽事以及伴隨一起的樂儀隊與啦啦隊表演已融入成為當地重要文化特色之一。

在美國以外,只有歐洲亦有一個由六支球隊組成的歐洲美式足球聯盟(NFL Europa),但已於2007年宣佈停辦比賽。在其他地方如日本、澳洲、墨西哥等,美式足球亦有流行,但只限於業餘或半職業賽事。

比賽規則

球場上的數字說明與離最近的達陣區之間的距離(單位:碼)

目標:美式足球的比賽目標是將橄欖球推進至對手的達陣區。同時在比賽規定時間內取得較對手更多的分數。

場地與球員

美式足球場通常被暱稱為烤肉架,因為球場上標示線的樣式讓球場看起來就像是一個可以幫助食物放在火上烤的架子。比賽是在一個120碼(110公尺)長、53 1/3碼(49公尺)寬的球場上進行比賽。較長的邊界稱為邊線(sideline),較短的邊界稱為底線(end line)。底線前的標示線稱為得分線(goal line),兩得分線之間的距離為100碼。得分的區域位於底線與得分線之間10碼寬的區域,稱為達陣區。

球場上每5碼距離標劃一條分碼線(yard lines),每10碼標示數字直到50碼線,或稱為中場區。在球場中間兩側劃有兩條標示線平行兩側邊線,稱為碼標(hash marks)。任何球員都必須在碼標線上或之間進行發球。

達陣區底部架設兩根球門柱,彼此間隔18.5英尺。球門柱由一根橫桿連結在一起,橫桿距離地面高度為10英尺。成功的射門,球必須穿越橫桿之上與兩根球門柱之間。

比賽時,雙方分別派出11位球員上場比賽。然而比賽進行時,可以隨時更換場上部分甚至全部的球員。球隊中全部53名球員皆可在每場比賽中被派出場比賽。每個球員皆有專屬的任務。球隊將球員們分成三組,分別為進攻組、防守組與特別組。

比賽時間

一場標準的比賽進行四節,每節15分鐘的比賽(中學比賽每節為12分鐘)以及包含第二、三節之間的中場休息。比賽進行中在一些情況下會暫停計時,因此比賽時間往往超出規定時間很多,達三個多小時之久。如果四節比賽後,雙方同分,比賽將會延長15分鐘,採用先得分者獲勝的規則。若仍無人得分,比賽結果以平手計。大學比賽的延長賽規定更為繁複與不同。

進攻方法

進攻隊形

美式足球進攻法與六人橄欖球相似。持球的一隊(進攻一方)有四次進攻機會向前(防守方的達陣區)推進十碼,每次機會稱為一個"檔"(down)。當進攻一方成功在四檔内累積推進了十碼(或超過),便可再次獲得继续进攻的四檔。如果進攻一方在四檔內都不能向前移動十碼,便要把球在第四檔進攻結束的位置交給對手。一般大多會在第四檔時採用棄踢(punt)將球權轉移給對手但令他們必須從較遠的地方開始進攻。

除了在開球、半場開球及得分後重新開球以外,每次進攻時,都要以相同的發球(snap)方式開始:進攻及防守組在開球線的前後兩邊排列,面向對方。其中一位進攻球員中鋒(Center)在兩腿之間把球向後傳給隊友,通常這位接球的隊友是四分衛(Quarterback)。

進攻一方有兩種方法推進:

  • 四分衛遞球給跑衛(Running Back)或其他任何有效的接球員(eligible receiver)持球向前跑,稱為跑陣(Rushing)
  • 把球傳給隊友,稱為傳球(Passing)。向前傳球是美式足球的特點。進攻一方在每次进攻机会只能向前傳球一次,而且必須在開球線以後向前傳,可以橫傳及向後傳無限次,但在進攻時橫後傳會有很大機會被攔截,因此美式足球很少橫傳或後傳,是一種難度極高的技巧。

每次進攻機會在以下的情況下完結,(稱為死球 Dead Ball)。裁判會吹哨子通知:

  • 持球的人被擒抱倒在地上,或裁判認為其進攻已被對方球員攔阻。
  • 向前傳的球出界,或在任何人接到之前已触地,稱為不成功傳球(Incomplete Pass);要把球放回原來的開球線上,這會用掉一檔的進攻然後再開始。
  • 持球的队员带球出界。
  • 其中一隊得分。

球員及觀眾經常需要知道當時是第幾次進攻,和還有多少碼才會重新再得四次機會。例如:第一檔進攻前,電視或計分板會寫:1st and 10,即是第一檔,且還差十碼才能取得第一檔。 如果一次進攻向前移了三碼,便會變成:2nd and 7,即第二檔,還差七碼取得一個10碼。

攻守交換

進攻一方可一路保有球,直至:

  • 進攻隊不能得到新的四次進攻機會。換句話說,進攻一方在四次進攻內都未能前進十碼。防守一方可在最後一次進攻完結的地方開始反攻。這種攻守交換稱為進攻失誤(Turnover on downs)。
  • 進攻達陣得分,或射門得分。進攻一隊接著踢開球(Kick-off)給對方。
  • 進攻方棄踢(Punt),方法是进攻队员(由特別組來執行)把球扔下并在球落地之前將其向前踢走。通常進攻一方如果在前三檔都未能成功前進十碼,而該處又未近至可以射門;為免在攻守交換後讓對方有機會可以在該處開始進攻,便會在第四檔時使用棄踢解圍。
  • 防守方的球員接到進攻方的傳球,稱之為攔截(Interception)。截得對方傳球的防守方球員可以立刻向對方達陣區移動,直至他被擒抱,出界,或得分。如果他未被任何原進攻方球員碰觸而造成手及腳以外的身體部位碰觸到地面,此時並不形成進攻結束(Down by Contact),它可以繼續跑直到被擒抱或被對方球員碰觸後倒在地上為止。同樣規則適用於進攻方的接球員。
  • 進攻方球員把球掉落到地上,稱掉球(Fumble),而又被防守方球員先拿到。與攔截一樣,防守方球員拿到對方掉球可以即時反攻,直至被擒抱,出界,或得分。进攻方的掉球和被攔截统称为失误。
  • 進攻的一方嘗試射門失敗。防守一方可在上一次開球處開始進攻(在NFL,是射門處)。如果射門處是底線前二十碼之內,原防守一方在二十碼线開始進攻。
  • 進攻一方在自己的達陣區內被擒抱,出界,或犯規,稱為安全得分(Safety),較為少見。

得分

攻守雙方以以下方法得分:

  • 达阵(Touchdown, 簡寫TD),得6分。當球員持球跑進對方達陣區,或在對方達陣區接到傳球(前提是落地之前沒有被擒抱而推出達陣區或掉球)時便是达阵。
    • 達陣之後,得分一隊獲一次追加得分(Extra Point)。球會放在對方的三碼線(NFL是兩碼線)上。得分隊可選擇把球射進門柱之內,加1分(稱為Field Goal);或以跑、傳等方法,再達陣一次,加2分(稱為2-Point Conversion)。在大學賽及職業賽中,多數都是以射門加一分。職業賽射入加1分的成功率為94%,大學亦有93.8%。而加2分的成功率只有43%左右。若果防守一方成功阻止加2分,並且把球搶到手,並且即時成功達成陣,可得2分(不适用于NFL)。
  • 射门(Field Goal, 簡寫FG),得3分。方法是把球踢過橫桿之上,及兩條門柱之間。射門時球必須先著地,通常是由置球員(Holder)負責把球按在地上,將球放於黑色踢球板上。通常当進攻方比较接近底线但又难以达阵时会在第四次檔选择射門而不是棄踢,又或者在时间紧迫无法用其他方式得分时选择射门得分。高中比賽射門失敗要將攻擊權交到防守方,但大學賽仍可以繼續進攻。
  • 安全得分(Safety),得2分。這是由防守球員得分。當進攻一方被迫後退至己方的達陣區,然後被擒抱或掉球時,防守一方得2分。某些进攻方在己方达阵区內的犯规也会被判安全得分。

踢开球和任意球

每个半场由踢开球开始。当一队达阵或射门得分后也进行踢开球。在职业联盟和大学联盟的比赛中,踢开球时分别把球放在己方的30码和35码线上的开球座上并踢出。对方的接球員试图接住来球并尽量向前推进,直至被擒抱、出界、掉球等無法再向前推進的情況下停止。然后进攻队就从他被擒抱的地点开始一系列的进攻。如果接球員不想带球推进,也可在接球前挥手示意,选择安全接球(Fair Catch)。

如果接球員(稱為Kick Returner)並未接好球而造成球落地(稱為Muff,常態為過去式Muffed),他可以自己撿起來後再推進,如果被守方球員碰到了,則要在守方球員碰到球的位置開始進行他們的第一檔且剩10碼重新取得第一檔(1st and 10)進攻。防守一方踢開球時可以大腳踢到底線,使進攻方離達陣區更遠;或者使用短踢(Onside kick),是將球輕輕踢出至十碼外的技巧,如接球方球員未拿到,開球方球員可以搶球,引發全員搶球大戰,如開球方成功得球,即可取回攻擊權開始進攻,假如失敗由原本接球方得球,接球方會有很好的進攻位置(球到中場,進攻方不用於底線開始進攻),一般用於急於扳回分數時。

犯规

当有犯规发生,犯规方会被判罚。大部分的判罚是把球向犯规方的达阵区退后一定的码数,一些防守方的犯规会判给进攻方新的四次进攻机会。如果防守方被罚退后的码数足够进攻方需要的码数,进攻方也会自动获得新的四次进攻。在比赛中发生犯规时裁判会在犯规地点附近扔小黄旗。在比赛停止后,没有犯规的一方有权选择接受判罚或接受当时的赛果。举例来说,当进攻方第一次进攻机会中成功推进了8码,而同时防守方越位或是提前移动,那么进攻方可以选择接受判罚,即向前推进5码并重新进行第一次进攻(还需推进5码);或者选择接受赛果也就是进行第二次进攻(还需推进2码).

常见犯规

  • 进攻方提前移动 (False Start):除了在开球线平行移动的一名球员外,进攻方队员在开球前移动。退后5码。
  • 越位 (Offside):在开球前队员越过了球的位置。退后5码。相似的犯规有:在开球前接触对方队员;越入中立区。
  • 阻挡(Holding):一名队员不公平地用拉球衣,勾人或铲人的方式妨碍对方有机会的阻截手或接球手。如果进攻方犯规或攻防转换中,退后10码;如果防守方犯规,退后5码和对方自动获得新的四次进攻机会。
  • 干扰传球(Pass Interference):当球传出后,防守队员推,勾,拉或击倒进攻方有机会接到传球的队员;或接球队员用同样的方式对付防守方队员以避免被对方截球。如果防守方犯规,进攻方可以選擇接受犯規或拒絕犯規,若攻方選擇接受,由開球線起計前進十五碼並自動重新獲得四次進攻;若攻方拒絕(通常出現在攻方在上一個交鋒成功推進十五碼之上,超過處罰的碼數),亦可由犯規地點重新開球,並同樣獲得四次新的進攻權。如果进攻方犯规,退后5码。如果在传球前有队员有类似犯规会被判阻挡或非法接触。
  • 個人犯規 (Personal Foul):處罰防守方,退後十五碼且對方自動獲得四下進攻。原因包六個項目:粗暴衝擊傳球者、粗暴衝擊踢球員、粗暴衝擊置球員(攻方射門中把皮球直立予踢球者射門的人員)、拉扯對方面罩、彎身用頭盔攔截對方、飛身在阻擋對方射門後畜意跳壓在對方身上(但不會被計算在犯規若守充方已在己方的一碼線。
  • 拖延比賽 (Delay Of Game):處罰四分衛,後退五碼處分,四十秒交鋒計時器數至零時仍未發球。
  • 非法向前傳球 (Illegal Forward Pass):攻方在攻防線之前向前傳球;後退五碼處分,並且會消耗一檔。
  • 進攻方非法陣式 (Illegal Formation):攻防線上少於七人列陣。
  • 場上有超過十一人 (Too Many Men On The Field):任何一方在發球時超過十一人在場上均會被罰,後退五碼。[注意:任何一方在交鋒上少於十人都是合法;在2007年季賽中華盛頓紅人為了紀念被在屋中被劫殺的安全衛尚·泰勒(Sean Taylor),特意在他死後的那周作客水牛城比爾的比賽上,防守以十人列陣。]
  • 非法變陣易位 (Illegal Shift):進攻方的球員可以在交鋒發球前移位,但只限列陣於攻防線以後的球員,並且每次只限一人,攻方要在隊友停下來後再可以進行易位,其他球員或者非法球員易位會變被處分五碼;防守方則不在此限。
  • 非法接球員前衝 (Illegal Man Downfield):攻方的合法接球員是指站於鋒線最外的兩員及所有衛員(發球線以後的球員);攻方在傳球攻擊時有上述球員以外的球員越過發球線都會被視為犯規,後退五碼。
  • 缺乏體育精神 (Unsportsmanlike Conduct):後退5碼處分,處罰的原因有很多種,會由主裁判決定。常見的有:畜意撞撃裁判,言語上辱罵裁判、故意延長得分後的慶祝、連續使用暫停凍結對方踢球員等(守方連續在踢球員踢球前叫兩次暫停,以凍結對方並增加心理壓力)。

若犯規被罰的碼數越過第一次進攻目標線,亦同樣自行獲得新的進攻權(例如:攻方在2nd And 3時,守方有球員越位,攻方可以獲得新的四次進攻)。 若攻守雙方被罰的後退的碼線位於達陣區,球會放在二碼線開始;若攻守方在已方的兩碼線內犯規,無論是幾多碼數的處罰,罰的碼數均會變成跟達陣區的一半距離,直至球的一部分進入達陣區,對手可獲得安全分(2009年超級盃,匹茲堡鋼人正好被處罰了一個相同情況的安全分)。

球員位置

美式足球有很多有著專門任務的球員位置。在大學聯賽及美國國家美式足球聯盟中,大部份球員只專注於進攻或防守的其中之一。

進攻組(進攻隊)

  • 由五名球員組成的攻擊線鋒(Offensive Line, OL, O-Line)負責保護傳球者(通常為四分衛)及阻擋對手來為己方跑手開路。除了中鋒外,其他攻擊線鋒通常不會觸及球。進攻線之列陣之左至右依序為:左截锋(Left Tackle, LT)、左哨鋒(Left Guard, LG)、中鋒(Center, C)、右哨鋒(Right Guard. RG)及右截锋(Right Tackle, RT)。由中鋒負責發球(Snap),故中鋒與四分衛之配合是進攻之始。
  • 四分衛(Quarterback, QB,有譯作「主帥」)在大部份進攻中都會接到發球。他可以給球(handoff)或傳、拋球給跑衛、外接員、或自己持球衝鋒。
  • 邊鋒(Tight End, TE,或称为近端锋)可列隊於兩攻擊絆鋒的外側,左右不拘,通常為右方。一般情況下只會有一個邊鋒,如兩絆鋒旁均列隊邊鋒,則外接員會退到進攻線後以碼以外的地方。他們可以像外接員去接球,也可以像攻擊線鋒們一樣去保護四分衛或為衝鋒球員開路。
  • 跑衛(Running Back, RB,或譯跑鋒)列陣時通常排在四分衛的後面或旁邊。他們是最擅長於持球衝鋒。他們也能做阻擋、接球、以及在比較罕見的情況下,將球拋、傳給隊友。

跑衛又細分為兩種

  • 全衛(Fullback, FB)多列隊於四分衛後面或旁邊,主要任務是幫四分衛阻擋或幫中衛開路阻擋,偶爾需要持球衝鋒與接球
  • 中衛(Halfback, HB)通稱的跑衛,在I陣式(I Formation)時列隊於全衛正後方,跑陣時大多數時間球是交到他們手上,有時也要充當外接員(多於霰彈槍陣式下)

 

  • 外接員(Wide Receiver, WR)在接近邊線地方列陣。他們擅長於接傳球。

外接員又細分為三種

  • 側衛(Flanker, FL),視邊鋒列隊位置而定,不跟邊鋒列隊於同一側,且在攻防線上
  • 翼鋒(Split End, SE),視邊鋒列隊位置而定,跟邊鋒列隊於同一側,且不列隊在攻擊線上而是在後場
  • 絆衛(Slotback, SB),會於霰彈槍陣式出現至少一位,列隊於攻防線與外接員之間的後場。主要工作是要阻擋、接球、甚至充當跑衛持球衝鋒,主要工作是阻擋跟接球

以上球員不會在每一次交鋒出場。球隊在每次交鋒可選擇派出多少名外接員、邊鋒及跑衛出場。

根據陳國亮先生所着的"美式足球觀賞入門"一書內,列隊於攻防線上或後一碼內的叫做"鋒",一碼後的叫做"衛",因此跑鋒較正確的翻譯應稱為跑衛

防守組(防守隊)

  • 防守線鋒(Defensive Line, DL)由三至五名在對手的進攻線鋒前列陣的球員組成。他們負責嘗試去在對方跑手衝鋒前或對方四分衛傳球前把他們擒抱。
  • 線衛(Linebacker, LB)。他們於防守線及後衛之間列陣,可以選擇衝向對方四分衛、擒抱跑衛或協助看守外接員。

防守線鋒與線衛合稱"前線七員(Front Seven)",一般有4防守線鋒3線衛 或 3防守線鋒4線衛陣式,前者稱為4-3防禦,後者稱為3-4防禦

如採4-3防禦則防守線上兩側為防守邊鋒(Defensive End,DE),中央為防守絆鋒(Defensive Tackle,DT),線衛兩側為外線衛(Outside Linebacker,OLB),中間為中線衛(Middle Linebacker,MLB)

如採3-4防禦則防守線上兩側為防守邊鋒,中央為正絆鋒(Nose Tackle,NT),線衛兩側為外線衛,中間為內線衛(Inside Linebacker,ILB)

  • 防守後衛(Defensive Backs,DB)通常由四名球員組成(兩名角衛(Cornerback, CB),強衛(Strong Safety, SS)及游衛/自由衛(Free Safety, FS)各一)。他們負責看守對方的外接員及避免他們成功接球。有時他們也會衝向對方的四分衛做閃電突擊(Blitz)試圖擒殺(Sack)對方四分衛。

線衛通常會在霰彈槍陣式下抽出1-3名來當作第三-第五個角衛,這時防守陣式會變為4-2-5、4-1-6、3-1-7、4-0-7甚至0-4-7(由愛國者教練Bill Belichick所創)

  • 五分衛(Nickelback, NB),為第三個角衛,第五個防守後衛
  • 十分衛(Dimeback),為第四個角衛,第六個防守後衛
  • 防守四分衛(Defensive Quarterback)或元衛(Dollarback),為第五個角衛,第七個防守後衛

如果再抽出一名線鋒,防守陣式變為3-0-8

  • 防守中衛(Defensive Halfback),為第六個角衛,第八個防守後衛

特別組(特別隊)

特別組是指那些負責在踢球時上場的球員們。特別組包括司有專職的球員有以下幾種

  • 棄踢員(Punter,P),負責棄踢
  • 踢球員(Kicker,K),負責開球、射門及追加得分射門

在大學以下的球隊通常會一人兼任以上兩個位置

 

  • 長發球員(Long Snapper,LS),專責在射門、棄踢情況下發球的中鋒
  • 置球員(Holder,H),負責在射門及追加得分射門時接長發球員的發球並擺放於地面或踢球板上,多為候補四分衛或棄踢員擔任。

 

  • 開球回攻員(Kick Returner,KR),負責接開球回攻
  • 棄踢回攻員(Punt Returner,PR),負責接棄踢回攻

以上兩個位置多為外接員或跑衛擔任

 

  • Gunner,G,負責擒抱回攻員的踢球方球員

基本戰術

對很多美式足球的球迷來說,最吸引他們的地方就是比賽雙方教練團在場上的鬥智。每一隊都有一本兵書(playbook),內有幾十到超過數百種的交鋒策略計謀。這些計謀會指導各球員在那次交鋒中的走位及要做的事。有一些交鋒計謀較為保守,大概只能攻下對方幾碼而已;有些計謀則有能力攻下對方大量碼數,但相對地自己丟失陣地甚或失控球的機會亦大增。

一般來說,跑陣比傳球較為安全。不過,亦有一些較為保守的傳球及較為冒險的跑陣。為了掩人耳目,有些傳球陣會擺出一款跑陣衝球的樣子,反過來的亦有。美式足球有很多詭計或花招,例如有時會排出踢球的陣型,但又突然嘗試去傳球或持球衝鋒去爭取第一進攻機會。成功的高風險計謀都會看得球迷們興奮不已。當然,如果對手已經洞悉了計謀的話,亦會為球隊帶來不幸的下場。

有說最近似真正行軍打仗的運動就是美式足球。也許就是這原因,美式足球在美國軍人中毫無疑問是最受歡迎的。事實上,美國軍事學院美國海軍學院美國空軍學院都有校隊參加美國大學聯賽NCAA的I-A組賽事。其中陸軍及海軍更有著悠久及著名的體育對抗歷史。

激烈的體能運動

美式足球是一種衝撞型的運動。為了制止攻方向前推進,守方須擒抱攔截持球的對方球員。因此,防守組員會透過身體接觸,在符合球例下把對手攔下。球例列明防守的擒抱者不能踢、打或絆倒對手。防守也不可拉對方的面罩、用自己的頭盔來攔截、或把對手抱起再摔下。除了這些及另外一些關於「過份粗暴」攔截的規則外,其他方式的擒抱都視為合法。負責阻擋開路的進攻球員以及要避開阻擋的防守球員有很大的空間及方法去令對方失手。四分衛更經常因視線未能察覺而受到防守球員以極速撞倒。

極多的身體衝擊令美式足球比其他美國流行的隊際運動來得危險。為此,球員們都須穿上很多的特別保護裝備,例如加墊的塑膠頭盔、護肩、護臀及護膝。這些護墊是在幾十年前開始推出,而一直以來都在改進中以達到減低球員創傷的目的。

雖然有保護裝備及相關球例去保障安全,然而美式足球的玩法令受傷依然常見。根據美國「國家嚴重體育傷患研究中心」(National Center for Catastrophic Sport Injury Research)資料顯示,廿五名美式足球員,當中大部份為高中生,在二零零零至二零零四年間因美式足球的受傷而死亡。腦震盪是其中一種常見的傷患。根據「亞利桑那州腦損傷協會」(Brain Injury Association of Arizona)的資料,每年有大約六萬二千名高中生受到腦震盪。比賽中受傷很常見,甚至偶有死亡的例子。在美國國內的後園、公園的消遣或業餘比賽中,因為沒有合規格的裝備而令受傷風險更高。

有人批評美式足球為一暴力運動。美式足球在跟籃球、(英式)足球及其他美國流行的運動比較起來的確有較多激烈碰撞。擒抱式美式足球在很多的美國校園都被禁止,改為玩用雙手觸碰來取代擒抱的觸碰式美式足球。體育課大多採用這種雙手觸碰式,而課後的學校體育運動則由於可提供合適的裝備及指導而玩擒抱式美式足球。

另外,激烈的身體碰撞及受傷的高風險令美式足球不太能吸引女性。通常女性在肌肉及重量上的不足會令她們比賽時有著較高的危險。而且,須要擒抱攔截的美式足球令強壯的大塊頭及敏捷的球員較有利。過去幾年,NFL球員的平均體重有上升的趨勢。

以上各種因素綜合起來引發的爭論,令美式足球在過去幾十年跟躲避球、摔角、冰球及拳擊等同被列為「暴力」運動。批評者指這些運動都側重在身型大小、體力、蠻力,引起小孩子不健康的好勇鬥狠及比賽心理。但亦有人指出體育帶出體育精神——雖然有身體接觸的運動都有一定程度的暴力在內,但它們總是強調技術及戰術而不是它的好戰性。

面對的問題

儘管過去九十多年不停地改例(例如禁止「馬軛式擒抱」)令美式足球的受傷率降低,但相對於其他運動之下還是要高。不過,保護裝備已日益改進,例如十九世紀九十年代非必須戴上的皮製頭盔就逐步改至今天的高科技有墊塑膠加面罩頭盔。

較近年則有在職業、大學、甚至高中的美式足球聯賽中掀起了關於使用違禁藥物的爭議的問題。

另一項問題是要玩美式足球花費不非。特別的頭盔、制服、墊子等非得要花幾百美元不可。一般的看法是學校及公眾消遣的足球聯賽需用去很多的財政預算;但大學校際足球(及某程度上的高中校際足球)都能夠靠賣入場門票而獲得利潤。很多時候校隊的該年表現足以決定校友該年捐款額的多寡,特別是是否擊敗宿敵學校。

參見

外部連結

American football

American football

The New England Patriots (blue) playing offense, against the Philadelphia Eagles (white) in an NFL game.

Nickname(s)

Football, Tackle football, Gridiron football

First played

November 6, 1869, Rutgers vs. Princeton

Characteristics

Contact

Collision

Team members

11 at a time

Categorization

Outdoor

Equipment

Football

Olympic

No

For other uses, see American football (disambiguation).

American football, known in the United States simply as football and often as gridiron or tackle football outside the United States, is a competitive team sport known for combining strategy with physical play. The objective of the game is to score points by advancing the ball into the opposing team's end zone. The ball can be advanced by carrying it (a running play) or by throwing it to a teammate (a passing play). Points can be scored in a variety of ways, including carrying the ball over the opponent's goal line, catching a pass thrown over that goal line, kicking the ball through the goal posts at the opponent's end zone, or tackling an opposing ball carrier within his end zone. The winner is the team with the most points when the time expires.

American football is closely related to Canadian football, but with significant differences.[1]

In the United States, the major forms are high school football, college football and professional football, which are essentially similar but feature slightly different rules.[2]

High school football is governed in the U.S. by the National Federation of State High School Associations. College football is governed in the U.S. by two bodies; the National Collegiate Athletic Association and the National Association of Intercollegiate Athletics. The major league for professional football is the National Football League. Over the years, there have been other notable professional football leagues, including the All America Football Conference during the 1940s, the American Football League during the 1960s, the United States Football League during the 1980s, and the currently active United Football League.

The sport is also played outside the United States. National professional and collegiate leagues exist in United Kingdom, Germany, Italy,[3] Switzerland,[4] Finland, Sweden,[5] Japan, Mexico, Israel,[6] Spain, Austria,[7] and several Pacific Island nations.

Contents

History

Main article: History of American football

An American football team at the turn of the twentieth century

The history of American football can be traced to early versions of rugby football and association football. Both games have their origins in varieties of football played in the United Kingdom in the mid-19th century, in which a ball is kicked at a goal and/or run over a line. Many games known as "football" were being played at colleges and universities in the United States in the first half of the 19th century.[8] [9]

Walter Camp

American football resulted from several major divergences from rugby football, most notably the rule changes instituted by Walter Camp, considered the "Father of American Football". Among these important changes were the introduction of the line of scrimmage and of down-and-distance rules. In the late 19th and early 20th centuries, game play developments by college coaches such as Eddie Cochems, Amos Alonzo Stagg, Knute Rockne, and Glenn "Pop" Warner helped take advantage of the newly introduced forward pass.

The popularity of collegiate football grew as it became the dominant version of the sport for the first half of the twentieth century. Bowl games, a college football tradition, attracted a national audience for collegiate teams. Bolstered by fierce rivalries, college football still holds widespread appeal in the US.[10][8][11]

The origin of professional football can be traced back to 1892, with William "Pudge" Heffelfinger's $500 contract to play in a game for the Allegheny Athletic Association against the Pittsburgh Athletic Club. The first Professional "league" was the Ohio League, formed in 1903, and the first Professional Football championship game was between the Buffalo Prospects and the Canton Bulldogs in 1919. In 1920, the American Professional Football Association was formed. The first game was played in Dayton, Ohio on October 3, 1920 with the host Triangles defeating the Columbus Panhandles 14–0. The league changed its name to the National Football League (NFL) two years later, and eventually became the major league of American football. Initially a sport of Midwestern industrial towns in the United States, professional football eventually became a national phenomenon. Football's increasing popularity is usually traced to the 1958 NFL Championship Game, a contest that has been dubbed the "Greatest Game Ever Played". A rival league to the NFL, the American Football League (AFL), began play in 1960; the pressure it put on the senior league led to a merger between the two leagues and the creation of the Super Bowl, which has become the most watched television event in the United States on an annual basis.[12]

Rules

Main article: American football rules

Field and players

The numbers on the field indicate the number of yards to the nearest end zone.

American football is played on a field 360 by 160 feet (109.7 by 48.8 m).[13] The longer boundary lines are sidelines, while the shorter boundary lines are end lines. Sidelines and end lines are out of bounds. Near each end of the field is a goal line; they are 100 yards (91.4 m) apart. A scoring area called an end zone extends 10 yards (9.1 m) beyond each goal line to each end line. The end zone includes the goal line but not the end line.[13] While the playing field is effectively flat, it is common for a field to be built with a slight crown—with the middle of the field higher than the sides—to allow water to drain from the field.

Yard lines cross the field every 5 yards (4.6 m), and are numbered every 10 yards from each goal line to the 50-yard line, or midfield (similar to a typical rugby league field). Two rows of short lines, known as inbounds lines or hash marks, run at 1-yard (91.4 cm) intervals perpendicular to the sidelines near the middle of the field. All plays start with the ball on or between the hash marks. Because of the arrangement of the lines, the field is occasionally referred to as a gridiron.

At the back of each end zone are two goalposts (also called uprights) connected by a crossbar 10 feet (3.05 m) from the ground. For high skill levels, the posts are 18 feet 6 inches (5.64 m) apart. For lower skill levels, these are widened to 23 feet 4 inches (7.11 m).

Each team has 11 players on the field at a time. However, teams may substitute for any or all of their players, if time allows, during the break between plays. As a result, players have very specialized roles, and, sometimes (although rarely) almost all of the (at least) 46 active players on an NFL team will play in any given game. Thus, teams are divided into three separate units: the offense, the defense and the special teams.

Start of halves

Similarly to association football, the game begins with a coin toss to determine which team will kick off to begin the game and which goal each team will defend.[14] The options are presented again to start the second half; the choices for the first half do not automatically determine the start of the second half. The referee conducts the coin toss with the captains (or sometimes coaches) of the opposing teams. The team that wins the coin toss has three options:[14]

  1. They may choose whether to kick or receive the opening kickoff.
  2. They may choose which goal to defend.
  3. They may choose to defer the first choice to the other team and have first choice to start the second half.[15]

Whatever the first team chooses, the second team has the option on the other choice (for example, if the first team elects to receive at the start of the game, the second team can decide which goal to defend).

At the start of the second half, the options to kick, receive, or choose a goal to defend are presented to the captains again. The team which did not choose first to start the first half (or which deferred its privilege to choose first) now gets first choice of options.[14][16]

Game duration

A standard football game consists of four 15-minute quarters (12-minute quarters in high-school football and often shorter at lower levels),[17] with a 12 minute half-time intermission after the second quarter.[18] The clock stops after certain plays; therefore, a game can last considerably longer (often more than three hours in real time), and if a game is broadcast on television, TV timeouts are taken at certain intervals of the game to broadcast commercials outside of game action. If an NFL game is tied after four quarters, the teams play an additional period lasting up to 15 minutes. In an NFL overtime game, the first team that scores wins, even if the other team does not get a possession; this is referred to as sudden death. In a regular-season NFL game, if neither team scores in overtime, the game is a tie. In an NFL playoff game, additional overtime periods are played, as needed, to determine a winner. College overtime rules are more complicated and are described in Overtime (sport).

A line of scrimmage on the 48-yard line. The offense is on the left.

A quarterback searching for opportunity to throw a pass.

A running back being tackled when he tries to run with the ball.

A quarterback preparing to throw a pass.

Forward pass in progress, during practice.

A kicker attempts an extra point.

Advancing the ball

Advancing the ball in American football resembles the six-tackle rule and the play-the-ball in rugby league. The team that takes possession of the ball (the offense) has four attempts, called downs, in which to advance the ball at least 10 yards (9.1 m) toward their opponent's (the defense's) end zone. When the offense succeeds in gaining at least 10 yards, it gets a first down, meaning the team has another set of four downs to gain yet another 10 yards or to score. If the offense fails to gain a first down (10 yards) after 4 downs, the other team gets possession of the ball at the point where the fourth down ended, beginning with their first down to advance the ball in the opposite direction.

Except at the beginning of halves and after scores, the ball is always put into play by a snap. Offensive players line up facing defensive players at the line of scrimmage (the position on the field where the play begins). One offensive player, the center, then passes (or "snaps") the ball backwards between his legs to a teammate behind him, usually the quarterback.

Players can then advance the ball in two ways:

  1. By running with the ball, also known as rushing.
  2. By throwing the ball to a teammate, known as a pass or as passing the football. If the pass is thrown down-field, it is known as a forward pass. The forward pass is a key factor distinguishing American and Canadian football from other football sports. The offense can throw the ball forward only once during a down and only from behind the line of scrimmage. However, the ball can be handed-off to another player or thrown, pitched, or tossed sideways or backwards (a lateral pass) at any time.

A down ends, and the ball becomes dead, after any of the following:

  • The player with the ball is forced to the ground (a tackle) or has his forward progress halted by members of the other team (as determined by an official).
  • A forward pass flies beyond the dimensions of the field (out of bounds) or touches the ground before it is caught. This is known as an incomplete pass. The ball is returned to the most recent line of scrimmage for the next down.
  • The ball or the player with the ball goes out of bounds.
  • A team scores.

Officials blow a whistle to notify players that the down is over.

Before each down, each team chooses a play, or coordinated movements and actions, that the players should follow on a down. Sometimes, downs themselves are referred to as "plays."

Change of possession

The offense maintains possession of the ball unless one of the following things occurs:

  • The team fails to get a first down— i.e., in four downs they fail to move the ball past a line 10 yards ahead of where they got their last first down. The defensive team takes over the ball at the spot where the 4th-down play ends. A change of possession in this manner is commonly called a turnover on downs.
  • The offense scores a touchdown or field goal. The team that scored then kicks the ball to the other team in a special play called a kickoff.
  • The offense punts the ball to the defense. A punt is a kick in which a player drops the ball and kicks it before it hits the ground. Punts are nearly always made on fourth down, when the offensive team does not want to risk giving up the ball to the other team at its current spot on the field (through a failed attempt to make a first down) and feels it is too far from the other team's goal posts to attempt a field goal.
  • A defensive player catches a forward pass. This is called an interception, and the player who makes the interception can run with the ball until he is tackled, forced out of bounds, or scores.
  • An offensive player drops the ball (a fumble) and a defensive player picks it up. As with interceptions, a player recovering a fumble can run with the ball until tackled, forced out of bounds, or scores. Backward passes that are not caught do not cause the down to end like incomplete forward passes do; instead the ball is still live as if it had been fumbled. Lost fumbles and interceptions are together known as turnovers.
  • The offensive team misses a field goal attempt. The defensive team gets the ball at the spot where the previous play began (or, in the NFL, at the spot of the kick). If the unsuccessful kick was attempted from within 20 yards (18.3 m) of the end zone, the other team gets the ball at its own 20 yard line (that is, 20 yards from the end zone). If a field goal is missed or blocked and the ball remains in the field of play, a defensive player may pick up the ball and attempt to advance it.
  • While in his own end zone, an offensive ball carrier is tackled, forced out of bounds, loses the ball out of bounds, or the offense commits certain fouls. This fairly rare occurrence is called a safety.
  • An offensive ball carrier fumbles the ball forward into the opposing end zone, and then the ball goes out of bounds. This extremely rare occurrence leads to a touchback, with the ball going over to the opposing team at their 20 yard line (Note that touchbacks during non-offensive special teams plays, such as punts and kickoffs, are quite common).

Scoring

A team scores points by the following plays:

  • A touchdown (TD) is worth 6 points.[18] It is scored when a player runs the ball into or catches a pass in his opponent's end zone.[18] A touchdown is analogous to a try in rugby. Unlike rugby, a player does not have to touch the ball to the ground to score; a touchdown is scored any time a player has possession of the ball while the ball is on or beyond the opponents' goal line (or the plane above it).
    • After a touchdown, the scoring team attempts a try (which is also analogous to the conversion in rugby). The ball is placed at the other team's 3-yard (2.7 m) line (the 2-yard (1.8 m) line in the NFL). The team can attempt to kick it over the crossbar and through the goal posts in the manner of a field goal for 1 point (an extra point or point-after touchdown (PAT)[19]), or run or pass it into the end zone in the manner of a touchdown for 2 points (a two-point conversion). In college football, if the defense intercepts or recovers a fumble during a one or two point conversion attempt and returns it to the opposing end zone, the defensive team is awarded the two points.
  • A field goal (FG) is worth 3 points, and it is scored by kicking the ball over the crossbar and through the goal posts (uprights).[18] Field goals may be placekicked (kicked when the ball is held vertically against the ground by a teammate) or drop-kicked (extremely uncommon in the modern game, with only two successes in sixty-plus years in the NFL). A field goal is usually attempted on fourth down instead of a punt when the ball is close to the opponent's goal line, or, when there is little or no time left to otherwise score.
  • A safety, worth 2 points, is scored by the opposing team when the team in possession at the end of a down is responsible for the ball becoming dead behind its own goal line. For instance, a safety is scored by the defense if an offensive player is tackled, goes out of bounds, or fumbles the ball out of bounds in his own end zone.[18] Safeties are relatively rare. Note that, though even more rare, the team initially on offense during a down can score a safety if a player of the original defense gains possession of the ball in front of his own goal line and then carries the ball or fumbles it into his own end zone where it becomes dead. However, if the ball becomes dead behind the goal line of the team in possession and its opponent is responsible for the ball being there (for instance, if the defense intercepts a forward pass in its own end zone and the ball becomes dead before the ball is advanced out of the end zone) it is a touchback: no points are scored and the team last in possession keeps possession with a first down at its own 20 yard line. In amateur football, in the extremely rare instance that a safety is scored on a try, it is worth only 1 point.

Kickoffs and free kicks

Each half begins with a kickoff. Teams also kick off after scoring touchdowns and field goals. The ball is kicked using a kicking tee from the team's own 30-yard (27 m) line in the NFL and college football (as of the 2007 season). The other team's kick returner tries to catch the ball and advance it as far as possible. Where he is stopped is the point where the offense will begin its drive, or series of offensive plays. If the kick returner catches the ball in his own end zone, he can either run with the ball, or elect for a touchback by kneeling in the end zone, in which case the receiving team then starts its offensive drive from its own 20 yard line. A touchback also occurs when the kick goes out-of-bounds in the end zone. A kickoff that goes out-of-bounds anywhere other than the end zone before being touched by the receiving team is a foul, and the ball will be placed where it went out of bounds or 30 yards (27 m) from the kickoff spot, depending on which is more advantageous to the opposite team.[20] Unlike with punts, once a kickoff goes 10 yards and the ball has hit the ground, it can be recovered by the kicking team.[20] A team, especially one who is losing, can try to take advantage of this by attempting an onside kick. Punts and turnovers in the end zone can also end in a touchback.

After safeties, the team that gave up the points must free kick the ball to the other team from its own 20 yard line.[21]

Penalties

A penalty flag on the field during a game on November 16, 2008 between the San Francisco 49ers and St. Louis Rams season.

Main article: Penalty (American football)

Fouls (a type of rule violation) are punished with penalties against the offending team. Most penalties result in moving the football towards the offending team's end zone. If the penalty would move the ball more than half the distance towards the offender's end zone, the penalty becomes half the distance to the goal instead of its normal value.

Most penalties result in replaying the down. Some defensive penalties give the offense an automatic first down.[22] Conversely, some offensive penalties result in loss of a down (loss of the right to repeat the down).[22] If a penalty gives the offensive team enough yardage to gain a first down, they get a first down, as usual.

If a foul occurs during a down, an official throws a yellow penalty flag near the spot of the foul. When the down ends, the team that did not commit the foul has the option of accepting the penalty, or declining the penalty and accepting the result of the down.

Variations

Variations on these basic rules exist, particularly touch and flag football, which are designed as non-contact or limited-contact alternatives to the relative violence of regular American football. In touch and flag football, tackling is not permitted. Offensive players are "tackled" when a defender tags them or removes a flag from their body, respectively. Both of these varieties are played mainly in informal settings such as intramural or youth games. Another variation is "wrap", where a player is "tackled" when another player wraps his arms around the ball carrier. Professional, intercollegiate, and varsity-level high school football invariably use the standard tackling rules.

Another variation is with the number of players on the field. In sparsely populated areas, it is not uncommon to find high school football teams playing nine-man football, eight-man football or six-man football. Players often play on offense as well as defense. The Arena Football League is a league that plays eight-man football, but also plays indoors and on a much smaller playing surface with rule changes to encourage a much more offensive game.

Another variation often played by American children is called Catch and Run. In this game, the children split into two teams and line up at opposite sides of the playing field. One side throws the ball to the other side. If the opposing team catches the ball, that player tries to run to the throwing teams touchdown without being tagged/tackled. If no one catches the ball or if the player is tagged/tackled, then that team has to throw the ball to the opposing team. This repeats until the game (or recess period) is deemed over.

Players

Main article: American football positions

See also: Formation (American football)

This diagram shows typical offensive and defensive formations. The offense (blue) consists of the quarterback (QB), fullback (FB), tailback (TB), wide receivers (WR), tight end (TE), and offensive linemen (C, OG, OT). The defense (red) consists of the defensive line (DL, DE), linebackers (LBs), cornerbacks (CB), strong safety (SS) and free safety (FS). Because teams can change any or all of the players between plays, the number of players at certain positions may differ on a given play. Here the offense is in the Normal I-Formation while the defense is in a 4-3 Normal.

Most football players have highly specialized roles. At the college and NFL levels, most play only offense or only defense.

Offense

  • The offensive line (OL) consists of five players whose job is to protect the passer and clear the way for runners by blocking members of the defense. The lineman in the middle is the Center. Outside the Center are the Guards, and outside them are the Tackles. Except for the center, who snaps the ball to one of the backs, offensive linemen generally do not handle the ball.
  • The quarterback (QB) receives the snap from the center on most plays. He then hands or tosses it to a running back, throws it to a receiver or runs with it himself. The quarterback is the leader of the offense and calls the plays that are signaled to him from the sidelines.
  • Running backs (RB) line up behind or beside the QB and specialize in running with the ball. They also block, catch passes and, on rare occasions, pass the ball to others or even receive the snap. If a team has two running backs in the game, usually one will be a halfback (HB) (or tailback (TB)), who is more likely to run with the ball, and the other will usually be a fullback (FB), who is more likely to block.
  • Wide receivers (WR) line up near the sidelines. They specialize in catching passes, though they also block for running plays or downfield after another receiver makes a catch.
  • Tight ends (TE) line up outside the offensive line. They can either play like wide receivers (catch passes) or like offensive linemen (protect the QB or create spaces for runners). Sometimes an offensive lineman takes the tight end position and is referred to as a tackle eligible.[23]

At least seven players must line up on the line of scrimmage on every offensive play. The other players may line up anywhere behind the line. The exact number of running backs, wide receivers and tight ends may differ on any given play. For example, if the team needs only 1 yard, it may use three tight ends, two running backs and no wide receivers. On the other hand, if it needs 20 yards, it may replace all of its running backs and tight ends with wide receivers.

Defense

In contrast to members of the offense, the rules of professional football (NFL Rulebook) and American college football NCAA Rulebook) do not specify starting position, movement, or coverage zones for members of the defensive team, except that they must be in the defensive zone at the start of play. The positions, movements and responsibilities of all defensive players are assigned by the team by selection of certain coverages, or patterns of placement and assignment of responsibilities. The positional roles are customary. These roles have varied over the history of American football. The following are customary defensive positions used in many coverages in modern American football.

  • The defensive line consists of three to six players who line up immediately across from the offensive line. They try to occupy the offensive linemen in order to free up the linebackers, disrupt the backfield (behind the offensive line) of the offense, and tackle the running back if he has the ball before he can gain yardage or the quarterback before he can throw or pass the ball. They are the first line of defense.
  • Behind the defensive line are the linebackers. They line up between the defensive line and defensive backs and may either rush the quarterback or cover potential receivers.
  • The last line of defense is known as the secondary, comprising at least three players who line up as defensive backs, who are either cornerbacks or safeties. They cover the receivers and try to stop pass completions. They occasionally rush the quarterback.

Special teams

The units of players who handle kicking plays are known as special teams. Three important special-teams players are the punter, who handles punts, the placekicker or kicker, who kicks off and attempts field goals and extra points, and the long snapper, who snaps the ball for extra points, field goals, and punts. Also included on special teams are the returners. These players return punts or kickoffs and try to get in good field position. These players can also score touchdowns.

Uniform numbering

Quarterback Shaun Carney has uniform number 5.

In the NFL, ranges of uniform numbers are (usually) reserved for certain positions:[24]

  • 1–19: Quarterbacks, kickers, and punters
  • 20–49: Running backs, Fullbacks, and defensive backs
  • 50–79: Centers
  • 50–79: Offensive Lineman
  • 10-19, 80–89: Wide receivers
  • 40-49, 80-89: tight ends
  • 60–99: Defensive linemen
  • 40-59, 90-99: Linebackers

NCAA and high school rules specify only that offensive linemen must have numbers in the 50-79 range, but the NCAA "strongly recommends" that quarterbacks and running backs have numbers below 50 and wide receivers numbers above 79. This helps officials as it means that numbers 50 to 79 are ineligible receivers, or players that may never receive a forward pass. There are no numbering restrictions on defensive players in the NCAA, other than that a team may not have two players on the field at the same time with the same jersey number.

Basic strategy

Main article: American football strategy

Because the game stops after every down, giving teams a chance to call a new play, strategy plays a major role in football. Each team has a playbook of dozens to hundreds of plays. Ideally, each play is a scripted, strategically sound team-coordinated endeavor. Some plays are very safe; they are likely to get only a few yards. Other plays have the potential for long gains but at a greater risk of a loss of yardage or a turnover.

Generally speaking, rushing plays are less risky than passing plays. However, there are relatively safe passing plays and risky running plays. To deceive the other team, some passing plays are designed to resemble running plays and vice versa. These are referred to as play-action passes and draws, respectively. There are many trick or gadget plays, such as when a team lines up as if it intends to punt and then tries to run or pass for a first down. Such high-risk plays are a great thrill to the fans when they work. However, they can spell disaster if the opposing team realizes the deception and acts accordingly.

The defense also plans plays in response to expectations of what the offense will do. For example, a "blitz" (using linebackers or defensive backs to charge the quarterback) is often attempted when the team on defense expects a pass. A blitz makes downfield passing more difficult but exposes the defense to big gains if the offensive line stems the rush.

Many hours of preparation and strategizing, including film review by both players and coaches, go into the days between football games. This, along with the demanding physicality of football (see below), is why teams typically play at most one game per week.

Physicality

Main articles: Health issues in American football and American football protective equipment

A halfback leads fellow backs through an agility drill at the Air Force Academy

American football is a collision sport. To stop the offense from advancing the ball, the defense must tackle the player with the ball by knocking or pulling him down. As such, defensive players must use some form of physical contact to bring the ball-carrier to the ground, within certain rules and guidelines. Tacklers cannot kick or punch the runner. They also cannot grab the face mask of the runner's helmet or lead into a tackle with their own helmet. Despite these and other rules regarding unnecessary roughness, most other forms of tackling are legal. Blockers and defenders trying to evade them also have wide leeway in trying to force their opponents out of the way. Quarterbacks are regularly hit by defenders coming on full speed from outside the quarterback's field of vision. This is commonly known as a blindside.

To compensate for this, players must wear special protective equipment, such as a padded plastic helmet, shoulder pads, hip pads and knee pads. These protective pads were introduced decades ago and have improved ever since to help minimize lasting injury to players. An unintended consequence of all the safety equipment has resulted in increasing levels of violence in the game. Players may now hurl themselves at one another at high speeds without a significant chance of injury. The injuries that do result tend to be severe and often season or career-ending and sometimes fatal. In previous years with less padding, tackling more closely resembled tackles in Rugby football. Better helmets have allowed players to use their helmets as weapons. This form of tackling is particularly unwise, because of the great potential for brain or spinal injury. All this has caused the various leagues, especially the NFL, to implement a complicated series of penalties for various types of contact. Most recently, virtually any contact with the helmet of a defensive player on the quarterback, or any contact to the quarterback's head, is now a foul. During the late 1970s, the penalty in high school football for spearing included ejection from the game.[25]

Despite protective equipment and rule changes to emphasize safety, injuries remain very common in football. It is increasingly rare, for example, for NFL quarterbacks or running backs (who take the most direct hits) to make it through an entire season without missing some time to injury. Additionally, 28 football players died from direct football injuries in the years 2000-05 and an additional 68 died indirectly from dehydration or other examples of "non-physical" dangers, according to the National Center for Catastrophic Sport Injury Research.[26] Concussions are common, with about 41,000 suffered every year among high school players according to the Brain Injury Association of Arizona.[27] In 1981, U.S. President Ronald Reagan, who played football in high school, commented on the contact of the sport: [Football] is the last thing left in civilization where men can literally fling themselves bodily at one another in combat and not be at war."[28]

Extra and optional equipment such as neck rolls, spider pads, rib protectors (referred to as "flak jackets"), and elbow pads help against injury as well, though they do not tend to be used by the majority of players due to their lack of requirement.

The danger of football and the equipment required to reduce it make regulation football impractical for casual play. Flag football and touch football are less violent variants of the game popular among recreational players.

Nutrition and dehydration

Football players typically begin their season while the weather is still extremely warm and with the dangerous combination of warm weather and high humidity, dehydration is a great risk for the players.[29] The players are usually required to follow a hydration schedule. It is extremely important for players to drink enough fluids because dehydration can seriously reduce athletic performance and increase the risk of heat illnesses. Most trainers and coaches make it imperative for their players to drink fluids before they are thirsty.[29]

Brain injury

The Concussions Committee of the NFL, co-chaired by Dr. Ira Casson, has generally denied that concussions result in permanent brain injury. However, there is some research, reported in 2009, which, using phone interviews based on the National Health Interview Survey, showed increased incidence of diagnosis of memory loss and dementia among retired professional football players. Such symptoms are believed related to the effects of concussion. More rigorous research is being conducted by Dr. Casson, neurologist, for the NFL. This finding is considered significant as such injuries may potentially affect high school and college players also.[30]

Organization in the United States

Main article: American football in the United States

Calendar

Traditionally, football is an autumn sport. A season typically begins in mid-to-late August and runs through December, into January. The professional playoffs run through January, and the Super Bowl is often played in the first week of February.

Amateurs playing on Thanksgiving

The NFL draft is usually held in April, in which eligible college football players are selected by NFL teams, the order of selection determined by the teams' final regular season records.

It is a long-standing tradition in the United States (though not universally observed) that high school football games are played on Friday night, college games on Saturday, and professional games on Sunday.

In the 1970s, the NFL began to schedule one game on Monday nights. Beginning in 2006, the NFL began scheduling games on Thursday and Saturday nights after the college football regular season concludes in mid-November, aired on the NFL Network.

In recent years, nationally televised Thursday night college games have become a weekly fixture on ESPN, and most nights of the week feature at least one college game, though most games are still played on the traditional Saturday.

Certain fall and winter holidays—such as the NFL's Thanksgiving Classic and numerous New Year's Day college bowl games—have traditional football games associated with them.

Despite this, there are a few professional leagues that have played in the spring, mainly to avoid competition with the established leagues. Examples include the now defunct XFL, the United States Football League, and the proposed All American Football League. Indoor football is played primarily in spring for this same reason.

At most levels of competition, college football teams hold several weeks of practices in the spring. These practices typically end with an intramural scrimmage open to the public. In certain areas, high school football teams also hold spring practices.

Outside the United States

Outside the United States, the sport is referred to as "American football" (or a translation thereof) to differentiate it from other football codes such as association football (soccer), rugby football, Australian rules football and Gaelic football. In Australia and New Zealand the game is also known as gridiron football, or more commonly as gridiron, although in the United States the term gridiron refers only to the playing field itself.[31] In much of the world, the term football is unambiguous and refers to association football (i.e. "soccer" in American English).

The NFL has attempted to introduce the game to other nations and operated a developmental league, NFL Europa, with teams in five German cities and one in the Netherlands, but this league folded following the 2007 season. The professional Canadian Football League and collegiate Canadian Interuniversity Sport play under the only slightly different Canadian rules.

In the UK, 46 teams play in the British American Football League. The BAFL has three levels: The Premier, of which there are five teams; BAFL 1, of which there are 19 teams; and BAFL 2, of which there are 26 teams. While the lower level teams have their own championship games during BritBowl Weekend, only Premier league teams face each other in the BritBowl which is it held in Doncaster's Keepmoat Stadium. Unlike the NFL, the BAFL season is played through the summer (April to September), with the British university season spanning the autumn and winter.

In Mexico, the ONEFA is a college league with 26 teams in 3 conferences.

In Japan, the X-League is a professional league with 60 teams in four divisions, using promotion and relegation. After the post-season playoffs, the X-League champion is determined in the Japan X Bowl. There are also over 200 universities fielding teams, with the national collegiate championship determined by the Koshien Bowl. The professional and collegiate champions then face each other in the Rice Bowl to determine the national champion.

In Germany, the German Football League whose elite division is called Bundesliga, has 12 teams partitioned into north and south conferences. The finalists from the playoffs determine the German champion during the German Bowl.

In Hungary, 18 registered teams participate in a the MAFL's two division league structure. The sport has grown significantly since 2004 and with some top Division I teams participating in the CEFL.

In Norway, div I consists of only two teams, Oslo Vikings and Eidsvoll 1814's. These two teams also compete in the European Football League but they play an annual game for the Norwegian Championship title. Norway has seven other teams that play in div II and this division is looked upon as the Norwegian Football League.

The International Federation of American Football is the governing body for American football with 45 member associations from North and South America, Europe, Asia and Oceania. The IFAF also oversees the American Football World Cup, which is held every four years. Japan won the first two World Cups, held in 1999 and 2003. Team USA, which had not participated in the previous World Cups, won the title in 2007.

Major American leagues have also held some regular season games outside of the United States. On October 2, 2005, the Arizona Cardinals and San Francisco 49ers played the first regular season NFL game outside of the United States, in Mexico City's Estadio Azteca,[32] From 2007, the NFL has played or has plans to play at least one regular season game outside of the United States. The NCAA will also play games outside of the U.S. In 2012, The United States Naval Academy will play the University of Notre Dame in Dublin, Ireland.[33]

See also

American football portal

References

Notes

  1. ^ In the United States and Canada, the term "football" may refer to either American football or to the similar sport of Canadian football, the meaning usually being clear from the context. This article describes the American variant.
  2. ^ See 2006 NCAA Football Rules and Interpretations, Sec. 1, Art. 1
  3. ^ "FIF - Federazione Italiana Football" (in Italian). FIF. 04 April 2009. http://www.federfootball.org/. Retrieved 2009-04-05. 
  4. ^ "SAFV - Schweizerischer American Football Verband" (in German). SAFV. http://www.safv.ch/. Retrieved 2009-05-19. 
  5. ^ Superserien on www.amerikanskfotboll.com (Swedish)
  6. ^ [SAFV - Schweizerischer American Football Verband "American Football in Israel"]. SAFV - Schweizerischer American Football Verband. Retrieved 2009-05-19. 
  7. ^ "American Football Bund Österreich". http://www.afboe.at/. Retrieved 2009-05-19. 
  8. ^ a b "What it was was Football!". Georgetown Magazine. Georgetown University Library Special Collections. http://www.library.georgetown.edu/special-collections/archives/essays/football. Retrieved 20010-02-07. 
  9. ^ Bath, Richard (ed.) The Complete Book of Rugby (Seven Oaks Ltd, 1997 ISBN 1 86200 013 3) p77
  10. ^ "Camp and His Followers: American Football 1876–1889". The Journey to Camp: The Origins of American Football to 1889. Professional Football Researchers Association. http://www.footballresearch.com/articles/frpage.cfm?topic=d-to1889. Retrieved 2007-05-16. 
  11. ^ "NFL History 1869–1910". NFL.com. NFL Enterprises LLC. 2007. http://www.nfl.com/history/chronology/1869-1910. Retrieved 2007-05-15. 
  12. ^ "NFL:America's Choice" (PDF). National Football League. 2007. http://www.coldhardfootballfacts.com/Documents/NFL_all_about_SB_1-07.pdf. Retrieved 2007-08-15. 
  13. ^ a b "NFL Football Field Dimensions". SportsKnowHow.com. 2004. http://www.sportsknowhow.com/football/field-dimensions/nfl-football-field-dimensions.html. Retrieved 2009-04-05. 
  14. ^ a b c "Coin Toss". NFL Enterprises LLC. 2009. http://www.nfl.com/rulebook/cointoss. Retrieved 2009-04-05. 
  15. ^ "NFL Makes Some Rule Changes". 2008. http://ap.google.com/article/ALeqM5gHSwbXq1wnH-jmEl-jV4W8M0Vd1wD8VQBFSG0. Retrieved 2008-04-03. 
  16. ^ "2005 Rules and Interpretations" (PDF). National Collegiate Athletic Association. 2005. http://www.ncaa.org/library/rules/2005/2005_football_rules.pdf. Retrieved 2008-01-09. 
  17. ^ Lawrence, Mark (2002–2005). "The Field". Mark Lawrence. http://football.calsci.com/TheRules4.html. Retrieved 2009-04-05. 
  18. ^ a b c d e "Beginner's Guide to Football". NFL Enterprises LLC. 2009. http://www.nfl.com/rulebook/beginnersguidetofootball. Retrieved 2009-04-05. 
  19. ^ 2007 Official Rules of the NFL. Triumph Books. 1 October 2007. ISBN 1699780288
  20. ^ a b "Kickoff". NFL Enterprises LLC.. 2009. http://www.nfl.com/rulebook/kickoff. Retrieved 2009-04-05. 
  21. ^ "Safety". NFL Enterprises LLC.. 2009. http://www.nfl.com/rulebook/safety. Retrieved 2009-04-05. 
  22. ^ a b "Penalty Summaries". NFL Enterprises LLC.. 2009. http://www.nfl.com/rulebook/penaltysummaries. Retrieved 2009-04-05. 
  23. ^ Member - Pro Football Hall of Fame
  24. ^ Troan, John (2002-02-24). "Player Numbers by Position". John Troan. http://www.jt-sw.com/football/pro/index.nsf/Documents/0-jers-nums. Retrieved 2009-04-05. 
  25. ^ Diehl, Jerry L., ed. 1999 and 2000 NFHS Football Handbook. Robert F. Kanaby, NFHS Publications. p. 20. 
  26. ^ Annual Survey of Football Injury Research 1931–2005, National Center for Catastrophic Sport Injury Research. Updated January 18, 2006. Accessed October 31, 2006
  27. ^ Studies Suggest 10% of Arizona High School Football Players Will Suffer a Concussion During This Coming Season PR Newswire press release from the Brain Injury Association of Arizona, August 23, 2005. Accessed October 31, 2006
  28. ^ D'Souza, Dinesh (February 23, 1999). Ronald Reagan: How an Ordinary Man Became an Extraordinary Leader. Free Press. p. 40. ISBN 0684848236
  29. ^ a b Hemmelgran, Melinda. "Nutrient Needs of Young Athletes." The Elementary School Journal: Sports and Physical Education 91 (1991): 445-56.
  30. ^ "Dementia Risk Seen in Players in N.F.L. Study" article by Alan Schwarz in The New York Times September 29, 2009
  31. ^ "gridiron." The American Heritage Dictionary of the English Language, Fourth Edition. Houghton Mifflin Company, 2004. 01 Oct. 2007. [1].
  32. ^ S.F. 49ers, Arizona Cardinals to kick off in Mexico - San Francisco Business Times:
  33. ^ "Notre Dame And Navy Extend Series 10 More Years :: Irish and Midshipmen will meet at least until 2016, with the 2012 meeting set to be in Dublin, Ireland". Und.cstv.com. http://und.cstv.com/sports/m-footbl/spec-rel/111005aac.html. Retrieved 2008-11-24. 

Bibliography

Further reading

  • Sports Illustrated magazine dated December 4, 2005; "Football America", a series of articles attesting to the pervasive popularity of American football in the United States at all levels.

External links

 

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