American football

The descriptions in this article are based primarily on the current rules of the National Football League (NFL, 1920-present). Differences with college rules will be noted. Professional, college, high school, and amateur rules are similar.

Professional leagues that no longer exist include the World Football League (WFL, 1974-75), the United States Football League (USFL, 1983-1985), the XFL (XFL, 2001), the All-America Football Conference (1946-1949) (only 3 or 4 teams are now in NFL), the World League of American Football (WLAF, 1991-1993 — now NFL Europe), and, the American Football League (AFL, 1960-1969). Only the AFL survives, as it merged with the NFL in 1970 and now exists (mostly) as the AFC.

The game

Object of the game

Methods of scoring

• A field goal, worth 3 points, is scored by kicking the ball between the uprights of the goal posts. In the NFL Europe league, Field Goals over 50 yards (measured as the distance from the point where the ball is kicked to the end line) attract 4 points.
• A touchdown, worth 6 points, is scored when the ball is advanced into the opponent's end zone. Immediately after a touchdown, the scoring team may run a single play called a try (more commonly called an extra point or conversion attempt) from just outside the end zone. They can either attempt to kick the ball through the uprights (worth one point, for a total of seven) or advance the ball into the end zone (worth 2, for a total of eight) on this play. College football and NFL Europe offer the non-scoring team the opportunity to score 2 points should they return a fumble, interception or blocked kick to the other team's end zone. In the NFL, a blocked extra point kick is blown dead immediately.
• A safety is a rare event occurring when a player causes the ball to become dead in his own end zone. When this occurs, the opposing team scores 2 points and gains posession from the ensuing safety kick from the 20 yard line. Typically this occurs when a ballcarrier is tackled in their own endzone, fumbles the ball out of their own endzone, or has a penalty assessed against them in their own end zone.
  

  Duration

  
  Collegiate and professional football games are 60 minutes long, divided into four quarters of 15 minutes each. Separating the second and third quarters is a halftime. If a game is tied at the end of four quarters, overtime is played. Professional overtime is played in 15-minute "sudden death" periods, meaning that the team that scores first, by any means, wins. In college football, a shootout style overtime system ensures that each team has equal opportunity to score. Many high schools play 12-minute quarters instead of 15.
  

  Kickoff

  
  A kickoff starts each half, and also restarts play following a field goal or touchdown. At the beginning of a half, the kicking team is determined by coin toss. After a team scores a field goal or touchdown, it kicks off the ball to its opponent. The ball is placed on a tee and kicked off at the kicking team's own 30-yard line in the NFL, or its own 35-yard line in college football. The ball is usually kicked as far as possible down the field, but sometimes a team will attempt to recover its own short kick, in a play known as an onside kick. The receiving team may catch and attempt to advance the ball at any time after the kick, but the kicking team may not touch the ball until it has traveled at least 10 yards.

Challenging plays

The officials may decide to review a play themselves if they do not all agree on the call. No team is charged with a challenge in this event. In the last two minutes ("two-minute warning") of each half and in overtime periods, the "red flag" system is suspended, and only officials can decide whether to review a play. This is meant to curb abuse of the system in which a team could enjoy two free time outs at the end of the game by saving their challenges beforehand.

This system was introduced in 1999. [1] An earlier rule for the use of "instant replay" to reverse referees' rulings existed for six seasons starting in 1986. This earlier system did not utilize the red flags; an extra referee, called the "Instant Replay Official", would himself decide whether to review each play. The old system was criticized for slowing the pace of many games, and was killed by the NFL owners after the 1991 season.

The field

to the nearest end zone.

The field is a rectangle 120 yards (ca. 110 m) long and 53 1/3 yards (50 m) wide, defined by sidelines running the length of the field and endlines running the width. There is a goal line ten yards in from each end line and parallel to it. The two goal lines are thus 100 yards (90 m) apart. The area of the field between the goal lines is called the field of play. At each end of the field, the end zone is the area between the goal line and the end line.

Within the field of play, additional markings include yard markers, as well as inbound lines (also called hash marks), every yard the length of the field. The inbound lines (hash marks), which are short lines perpendicular to the yard markers, differ in distance from the sidelines at each main level of the game:

At the center of each end line is a set of goal posts, which have two upright posts extending above a crossbar. The distance between upright posts is 18½ feet in general and 23 1/3 feet in high schools (5½ m, 7 m), and the top of the crossbar is 10 feet (3 m) above the ground.

Play of the game

The team with possession of the ball is called the offensive team, and the other team the defensive team. A set of downs begins with a first down, which is given to a team either after it has just gained possession on the previous play, or it has gained the necessary yardage from a previous set of downs. On a first down, the offensive team is given four downs to gain 10 yards. This is commonly referred to as "first and ten", meaning that it is first down, and ten yards are needed to get another first down. The line a team must reach in order to gain a first down is technically called the line to gain or the necessary line, although it is commonly called the first down line. In the event a team gains a first down and the new line of scrimmage is within ten yards of their opponent's goal line, the goal line becomes line to gain. This is commonly known as "first and goal," signifying that no more first downs can be achieved, and it is necessary to score on the current set of downs. Failure to gain the necessary yardage on a set of downs results in a "turnover on downs."

Plays from scrimmage

Advancing the ball

• Running the ball - The quarterback, who normally receives the snap, either hands the ball or throws a lateral pass to a running back, who then becomes the ball carrier. Most other players on the offense have blocking assignments, and attempt to prevent the defense from tackling the ball carrier. The quarterback may also run the ball himself.

• A forward pass - A forward pass may only be thrown on a play from scrimmage, and only from behind the line of scrimmage. It must be thrown to an eligible receiver (any player who is not an interior lineman). A completed pass is one caught by a member of the offense, although if the first player to touch the ball is not an eligible receiver, a penalty results. The player may run with the ball after catching it. To be considered "in bounds" a receiver must have clear possession of the ball and place both feet (NFL) or one foot (college) in bounds prior to stepping out of bounds. An incomplete pass is any forward pass that either hits the ground or goes out of bounds, at which point the ball becomes dead, and is spotted at the preceding line of scrimmage for the following play. An interception is a pass caught by the defense, which transfers possession to the defending team.

Fourth down situations

Offensive options on fourth down:

A team will occasionally run a trick play on fourth down. They will line up in a punting or field goal formation, but will instead run the ball or pass it in an attempt to pick up a first down.

Specialized units and players

A list of player types and definitions can also be found in the Glossary of American football.

Common penalties

Some of the most common penalties are listed below. For a more detailed discussion, see American football rules.

Note: The neutral zone is the space defined by lines drawn through the ends of the ball parallel to the yard lines when the ball is spotted and ready for play. No player may legally have any part of his body in the neutral zone when the ball is snapped, with the exception of the center.

Penalties against the offense

False start (5 yards) - any player moving after they have gotten in their set position before the snap in a way that simulates the start of the play

Delay of game (5 yards) - allowing the play clock to elapse before the snap

Holding (10 yards) - illegal use of the hands or arms while blocking; an automatic safety is assessed instead if spot of infraction is within the offensive team's own end zone.

Offensive pass interference (10 yards) - interfering with a defender attempting to catch a pass

Intentional grounding - throwing the ball into the ground to avoid being tackled

*NFL penalty: 10 yards or spot of foul, whichever is farther from the original line of scrimmage, and loss of down

*College penalty: Spot of foul and loss of down

*In both NFL and college, intentional grounding from the offensive team's own end zone constitutes an automatic safety unless the defense chooses to decline the penalty, which might only ever happen if the infraction had occurred on a fourth-down play. If the quarterback has moved outside of the area between his offensive tackles (the "pocket"), there is no penalty for grounding the ball if the quarterback throws the ball past the line of scrimmage. There is also no penalty for "spiking" the ball to stop the game clock, by throwing it directly into the ground. However, such an action must be executed immediately after the snap of the ball, before the quarterback demonstrates intent to make a forward pass.

Illegal blocks

*Illegal block in the back (10 yards) - an illegal block from behind and above the waist

*Clipping (15 yards) - an illegal block from behind and below the waist

*Illegal crackback block (15 yards) - an illegal block, from any direction, below the waist by any offensive player not on the offensive line (e.g. wide receivers, quarterbacks and running backs)

Penalties against the defense

Offsides (5 yards) - Being across the line of scrimmage before the ball is snapped, or being in the neutral zone when the ball is snapped. When called, the official throws a flag, but the play continues.

Encroachment (5 yards) - A "defensive false start," called when a defensive player contacts an offensive player or crosses the offensive line before the snap. When called, the official throws a flag and blows his whistle, stopping the play.

Running into the kicker (5 yards) - during a kick from scrimmage

Pass interference - interfering with a receiver's attempt to catch the ball.

*NFL: This can be a devastating penalty because the ball is moved forward to the location of the interference, as if it had been caught.

*College: An automatic first down. Penalty is 15 yards or the spot of the foul, whichever is closer to the previous line of scrimmage.

*High school: 15 yards and an automatic first down

Defensive holding or Illegal use of hands (5 yards and an automatic first down; in college, the chains are not moved if the previous play was 1st and 10, making the next play 1st and 5, as in "Offsides" or "Encroachment" above) - illegal use of the hands or arms either while attempting to ward off a block, or to cover a receiver

Illegal contact (informally, illegal chuck, 5 yards and an automatic first down; in college, same exception noted in "Defensive holding" above applies) - any contact made between a defender and a receiver after the latter has traversed more than five yards beyond the line of scrimmage; this rule was adopted in 1978, and its enactment is regarded as contributing to the dramatic increase in both passing yardage and scoring the NFL has witnessed since that time.

Piling on (15 yards and automatic first down) - unnecessarily falling on or jumping on any player who has already been downed

Roughing the kicker (15 yards and automatic first down) - tackling the kicker after he has kicked the ball

Roughing the passer (15 yards and automatic first down) - tackling the quarterback after he has thrown a forward pass. The defender is expected to make a reasonable effort to avoid the passer; if, once the ball is thrown, contact is imminent or inevitable, no penalty is called.

Penalties against either team

Too many players on the field (5 yards)

Grabbing the face mask (5 or 15 yards) - If there is pulling, twisting or turning, 15 yards; otherwise 5 yards. In college, any face mask penalty on the defense results in an automatic first down; in the NFL, only the 15-yard ("flagrant") face mask penalty results in an automatic first down, but in the case of a 5-yard penalty the down remains the same.

Unsportsmanlike conduct (15 yards) - Any conduct by anyone involved in the game—usually a player, but occasionally a coach, and very rarely one or more spectators—deemed to be especially objectionable by the game officials, or by rule. The penalty is more strictly enforced in college football than in the NFL.

Unnecessary roughness (15 yards) - Tackling or striking another player after the ball is dead or when the player is out of bounds. Repeated infractions or especially severe fouls may result in the player's ejection from the game.

Development of the game

Rugby was first introduced to North America in Canada, brought by the British Army garrison in Montreal which played a series of games with McGill University. In 1874, McGill arranged to play a few games in the United States, at Harvard University, which liked the new game so much that it became a feature of the Ivy League. Both Canadian and American football evolved from this point. For an in-depth overview of the differences and similarities of Canadian football and American football see: Comparison of Canadian and American football

American football in its current form grew out of a series of three games between Harvard University and McGill University of Montreal in 1874. McGill played rugby football while Harvard played the Boston Game, which was closer to soccer. As often happened in those days of far from universal rules, the teams alternated rules so that both would have a fair chance. The Harvard players liked having the opportunity to run with the ball, and in 1875 persuaded Yale University to adopt rugby rules for their annual game. In 1876 Yale, Harvard, Princeton, and Columbia formed the Intercollegiate Football Association, which used the rugby code, except for a slight difference in scoring.

In 1880 Walter Camp introduced the scrimmage in place of the rugby scrum. In 1882 the system of downs was introduced to thwart Princeton's and Yale's strategy of controlling the ball without trying to score. In 1883 the number of players was reduced, at Camp's urging, to eleven, and Camp introduced the soon standard arrangement of a seven-man offensive line with a quarterback, two halfbacks, and a fullback.

On September 3, 1895 the first professional football game was played, in Latrobe, Pennsylvania, between the Latrobe YMCA and the Jeannette Athletic Club. (Latrobe won the contest 12-0.).

By the 1890s interlocking offensive formations such as the flying wedge and the practice of teammates physically dragging ball-carrying players forward had made the game extremely dangerous. Despite restrictions on the flying wedge and other precautions, in 1905 eighteen players were killed in games. President Theodore Roosevelt informed the universities that the game must be made safer. To force them to respond to his concerns, he threatened to pressure Congress to make playing football a federal crime.

In 1906, two rival organizing bodies, the Intercollegiate Rules Committee and the Intercollegiate Athletic Association, met in New York; eventually they agreed on several new rules intended to make the game safer, among them the addition of a neutral zone between the scrimmage lines and a requirement that at least six players from each team line up on them. The most far-reaching innovation they considered, though, was the legalization of the forward pass. This was very controversial at the time, much derided by purists. As an alternative means of opening out the play, Walter Camp would have preferred widening the field; but representatives from Harvard pointed to recently constructed Harvard Stadium, which could not be widened, and the forward pass was adopted; it has come to shape the whole history of American football, as opposed to its cousins around the world.

In 1910, after further deaths, interlocking formations were finally outlawed; and in 1912 the field was changed to its current size, the value of a touchdown increased to 6 points, and a fourth down added to each possession. The game had achieved its modern form.

Beyond recreation and entertainment

Football scandals

Recent attitudes toward and awareness of steroid use are also evolving. Fans and critics actively debate the role of steroids in professional and amateur football.

Football and drugs

Since nutritional standards and weight-training technique were already quite advanced even in the 1960's, it has been conjectured that much of the increase in the size of the players is the result of the widespread availability of illegal anabolic steroids, which facilitate increased growth of muscle tissue. Such drugs are widely available even to high school players.

Because anabolic steroids have dangerous side effects, the National Football League tests its players for steroids, and penalizes those who are caught. However, it has recently emerged that new varieties of steroids are being developed in clandestine laboratories, which elude existing drug tests. Hence there is a kind of "arms race" between the scientists who develop new kinds of illegal steroids and those who develop tests to detect them.

Injuries

The NFL has a roster limit of 53 players per team during the season; 45 of which dress for a game plus an "emergency quarterback" who only plays if all the quarterbacks on the 45-man roster are out of the game. Players who are injured are frequently among the eight that do not dress. If it becomes certain that a player will not play for the rest of the season, the team may put him on the "Injured Reserve" list and replace the player on the roster.

An average of about eight players die each year in the United States as a result of injuries received in games at all levels. About 160 concussions occur every season, and the National Football League now collects benchmark measures of awareness for each player, which can be used during a game to judge whether he has been concussed.

Injuries sustained by football players often are permanent. Many former football players experience pain, sometimes severe, that lasts for the rest of their lives. Many players require surgery, even multiple surgeries, for injuries experienced years earlier.

Interestingly, newspaper reporters who have interviewed former football players who are crippled or in pain as a result of their former sport find that a player will never (or virtually never) express regret over his choice of career. The players often state that the thrill of playing football was worth the price of a lifetime of subsequent pain.

Deaths and long-term disability attributed to illegal use of anabolic steroids have become a new factor in this picture, starting in about the 1990s.

Instances of heat-related death, especially during professional practice sessions, have begun receiving press attention in the decade of the 2000s, and led to new standards intended to respond cautiously to possible danger signs that traditionally had been ignored. There is also the prospect that conventional first-aid technique has been in error, and an apparatus to circumvent this: apparently efforts to cool an overheated patient quickly, by wetting a large fraction of the body, are misguided, with the sudden chilling of the skin causing the body to reduce superficial circulation, and making that chilling near the surface ineffective at cooling the core of the body and thus the brain. A device suitable for professional teams has been developed, that provides for rapid cooling of small areas of skin where large blood vessels are near the surface, and is proposed as a means of cooling the blood quickly without evoking the reflex of isolating the body surface from the core.

Certain penalties have been implemented in an attempt to reduce the number of more serious injuries. An example of this is the illegal "crackback block", consisting of a block below the waist by a player entering the line of close play. These blocks are infamous for causing severe leg injuries.

References

See also

External links