In gridiron football, a shift refers to the movement of an offensive player prior to the snap.
There is a distinction drawn between a shift and motion in football. Motion occurs when a player is moving at the time of the snap. A shift occurs when one or more players changes their position on the offensive side of the ball before the snap, causing a change in formation. For example, players may line up initially in an I-formation and then shift the two running backs into wide receiver positions to put the offense in a spread formation. A team may shift any number of players into new positions, so long as they all come to a complete stop for a full second before the ball is snapped to start the play.
The National Football League (NFL) defines all motion and shift penalties as "illegal motion", [1] while both the NCAA and NFHSAA make a distinction between an "illegal shift" and "illegal motion"; an illegal shift refers to players shifting and not coming to a complete stop before the snap, while illegal motion refers to a player who is in motion towards the line of scrimmage, or a player who is not a "back" in motion. [2] In both leagues, however, the penalty for illegal motion/illegal shift is five yards from the previous spot and replay the down.
Additionally, the offensive team may be charged with the penalty of a "false start" if a player on the offense jumps or moves abruptly, simulating the start of the play. This movement is not normally considered a subset of the "motion" or "shift" rules, as the player is not judged to be moving into a new pre-snap position; they are merely starting the play too soon. This is also a five yard penalty.
Both motions and shift were introduced by Amos Alonzo Stagg. [3] The history of college football involves three notable, distinct shifts:
In gridiron football, not all players on offense are entitled to receive a forward pass: only an eligible pass receiver may legally catch a forward pass, and only an eligible receiver may advance beyond the neutral zone if a forward pass crosses into the neutral zone. If the pass is received by a non-eligible receiver, it is "illegal touching". If an ineligible receiver is beyond the neutral zone when a forward pass crossing the neutral zone is thrown, a foul of "ineligible receiver downfield" is called. Each league has slightly different rules regarding who is considered an eligible receiver.
A snap is the backward passing of the ball in gridiron football at the start of play from scrimmage.
In gridiron football, a line of scrimmage is an invisible transverse line beyond which a team cannot cross until the next play has begun. Its location is based on the spot where the ball is placed after the end of the most recent play and following the assessment of any penalty yards.
The quarterback (QB) is a position in gridiron football who are members of the offensive side of the ball and mostly line up directly behind the offensive line. In modern American football, the quarterback is usually considered the leader of the offense, and is often responsible for calling the play in the huddle. The quarterback also touches the ball on almost every offensive play, and is almost always the offensive player that throws forward passes. When the QB is tackled behind the line of scrimmage, it is called a sack. The position is also colloquially known as the "signal caller" and "field general".
The tight end (TE) is an offensive position in American football, arena football, and Canadian football. It is a hybrid that combines the characteristics and roles of both an offensive lineman and a receiver. As part of the receiver corps, they play inside the flanks (tight), contrasted with the split end who plays outside the flanks (wide). Like offensive linemen, they are usually lined up on the offensive line and are large enough to be effective blockers. On the other hand, unlike offensive linemen, they are eligible receivers and potent weapons in a team's offensive schemes.
Gridiron football, also known as North American football, or in North America as simply football, is a family of football team sports primarily played in the United States and Canada. American football, which uses 11 players, is the form played in the United States and the best known form of gridiron football worldwide, while Canadian football, which uses 12 players, predominates in Canada. Other derivative varieties include arena football, flag football and amateur games such as touch and street football. Football is played at professional, collegiate, high school, semi-professional, and amateur levels.
American and Canadian football are gridiron codes of football that are very similar; both have their origins partly in rugby football, but some key differences exist between the two codes.
Gameplay in American football consists of a series of downs, individual plays of short duration, outside of which the ball is or is not in play. These can be plays from scrimmage – passes, runs, punts or field goal attempts – or free kicks such as kickoffs and fair catch kicks. Substitutions can be made between downs, which allows for a great deal of specialization as coaches choose the players best suited for each particular situation. During a play, each team should have no more than 11 players on the field, and each of them has specific tasks assigned for that specific play.
A formation in American football refers to the position players line up in before the start of a down. There are both offensive and defensive formations and there are many formations in both categories. Sometimes, formations are referred to as packages.
Center or centre (C) is a position in American football. The center is the innermost lineman of the offensive line on a football team's offense. The center is also the player who passes the ball between his legs to the quarterback at the start of each play.
Slotback, also called S-back or A-back, is a position in gridiron football. The "slot" is the area between the offensive tackle and the wide receiver. A player who lines up between those two players and behind the line of scrimmage fills that "slot".
The A-11 offense is an offensive scheme that has been used in some levels of amateur American football. In this offense, a loophole in the rules governing kicking formations is used to disguise which offensive players would be eligible to receive a pass for any given play. It was designed by Kurt Bryan and Steve Humphries of Piedmont High School in California.
In gridiron football, motion refers to the movement of an offensive player at the time of the snap.
The following terms are used in American football, both conventional and indoor. Some of these terms are also in use in Canadian football; for a list of terms unique to that code, see Glossary of Canadian football.
Wildcat formation describes a formation for the offense in football in which the ball is snapped not to the quarterback but directly to a player of another position lined up at the quarterback position. The wildcat features an unbalanced offensive line and looks to the defense like a sweep behind zone blocking. A player moves across the formation prior to the snap. However, once this player crosses the position of the running back who will receive the snap, the play develops unlike the sweep.
In gridiron football, a penalty is a sanction assessed against a team for a violation of the rules, called a foul. Officials initially signal penalties by tossing a bright yellow colored penalty flag onto the field toward or at the spot of a foul.
In gridiron football, an ineligible receiver downfield, or an ineligible man downfield, is a penalty called against the offensive team when a forward pass is thrown while a player who is ineligible to receive a pass is beyond the line of scrimmage without blocking an opponent at the time of the pass. A player is determined ineligible based on his position at the time of the snap. When the ball is snapped, the offense is required to have no more than eleven players on the field, out of whom only six are eligible. On most plays, the eligible receivers include the quarterback, running backs, fullbacks, tight ends, and wide receivers, while the ineligible receivers are offensive linemen, including the center, offensive guards, and offensive tackles. However, in the National Football League, a quarterback is an ineligible receiver if he is directly under the center when he receives the snap.
The run and shoot offense is an offensive system for American football which emphasizes receiver motion and on-the-fly adjustments of receivers' routes in response to different defenses. It was conceived by former high school coach Glenn "Tiger" Ellison and refined and popularized by former Portland State offensive coordinator Mouse Davis.