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Defensive end (DE) is a defensive position in the sport of gridiron football.
This position has designated the players at each end of the defensive line,   but changes in formations over the years have substantially changed how the position is played.
Early formations, with six- and seven-man lines, used the end as a containment player, whose job was first to prevent an "end run" around his position, then secondarily to force plays inside.
When most teams adopted a five-man line, two different styles of end play developed: "crashing" ends, who rushed into the backfield to disrupt plays, and "stand-up" or "waiting" ends, who played the more traditional containment style. Some teams would use both styles of end play, depending on game situations.
Traditionally, defensive ends are in a three-point stance, with their free hand cocked back ready to "punch" an offensive lineman, or in a two-point stance like a strong safety so they can keep containment. Some defensive ends play the position due to their size; they close down their gap so the running back has no hole to run through. Other ends play the position due to their speed and agility; they are used to rush the quarterback. These ends can time the snap of the ball in order to get a jump on the rush, and stop the play.
Most of the time it is the job of the defensive end in run defense to keep outside or containment, which means that no one should get to their outside; they must keep everything to the inside. If they have an outside linebacker besides them that is not in pass coverage, this gives the defensive end more freedom to rush the quarterback. The defensive ends are fast for players of their size, often the fastest and smallest players on the defensive line. They must be able to shed blockers to get to the ball. Defensive ends are also often used to cover the outside area of the line of scrimmage, to tackle ball carriers running to the far right or left side, and to defend against screen passes. Since the creation of zone blitz defenses in the late 1990s, defensive ends have sometimes been used in pass coverage, dropping back to cover routes run close to the line of scrimmage.
In the 3–4 defense, defensive ends are used primarily as run stoppers and are much larger than the normal size of a player at this position. Often, the position is played by a more agile or slightly undersized defensive tackle. Because of the increased popularity of the 3–4 defense, the value of a defensive tackle prospect that can possibly be used in this manner has increased.[ citation needed ] They are used to occupy an offensive lineman, on pass rushing plays to let the outside linebackers get a sack. They block screen passes and are put outside the offensive tackles to get a sack. Defensive ends in the 3–4 defense average a height of 6′3″–6′8″ and a weight of 285–315 lbs.[ citation needed ]
A running back (RB) is a member of the offensive backfield in gridiron football. The primary roles of a running back are to receive handoffs from the quarterback to rush the ball, to line up as a receiver to catch the ball, and block. There are usually one or two running backs on the field for a given play, depending on the offensive formation. A running back may be a halfback, a wingback or a fullback. A running back will sometimes be called a "feature back" if he is the team's starting running back.
In gridiron football, a lineman is a player who specializes in play at the line of scrimmage. The linemen of the team currently in possession of the ball are the offensive line, while linemen on the opposing team are the defensive line. A number of NFL rules specifically address restrictions and requirements for the offensive line, whose job is to help protect the quarterback from getting sacked for a loss, or worse, fumbling. The defensive line is covered by the same rules that apply to all defensive players. Linemen are usually the largest players on the field in both height and weight, since their positions usually require less running and more strength than skill positions.
A cornerback (CB) is a member of the defensive backfield or secondary in gridiron football. Cornerbacks cover receivers most of the time, but also blitz and defend against such offensive running plays as sweeps and reverses. They create turnovers through hard tackles, interceptions, and deflecting forward passes.
A linebacker is a playing position in gridiron football. Linebackers are members of the defensive team, and line up approximately three to five yards behind the line of scrimmage and behind the defensive linemen. They represent the "middle ground" of defenders, playing closer to the line of scrimmage than do the defensive backs, but farther back than do the defensive linemen.
This is a glossary of terms used in Canadian football. The Glossary of American football article also covers many terms that are also used in the Canadian version of the game.
Strategy forms a major part of American football. Both teams plan many aspects of their plays (offense) and response to plays (defense), such as what formations they take, who they put on the field, and the roles and instructions each player are given. Throughout a game, each team adapts to the other's apparent strengths and weaknesses, trying various approaches to outmaneuver or overpower their opponent in order to win the game.
The 46 defense is an American football defensive formation, an eight men in the box defense, with six players along the line of scrimmage. There are two players at linebacker depth playing linebacker technique, and then three defensive backs. The 46 defense was originally developed and popularized with the Chicago Bears by their defensive coordinator Buddy Ryan, who later became head coach of the Philadelphia Eagles and Arizona Cardinals.
A formation in 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 (C) is a position in gridiron 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.
A trick play, also known as a gadget play, gimmick play or trickeration, is a play in gridiron football that uses deception and unorthodox tactics to fool the opposing team. A trick play is often risky, offering the potential for a large gain or a touchdown if it is successful, but with the chance of a significant loss of yards or a turnover if not. Trick plays are rarely used not only because of the riskiness, but also to maintain the element of surprise for when they are used.
In American football, the specific role that a player takes on the field is referred to as their "position". Under the modern rules of American football, both teams are allowed 11 players on the field at one time and have "unlimited free substitutions", meaning that they may change any number of players during any "dead ball" situation. This has resulted in the development of three task-specific "platoons" of players within any single team: the offense, the defense, and the so-called 'special teams'. Within these three separate "platoons", various positions exist depending on the jobs that the players are doing.
There are several defensive formations commonly used in eight-man football. Defensive formations are classified by the total number of linemen and linebackers in the formation. The three basic types of formations in eight-man football are seven-man fronts, six-man fronts and five-man fronts.
The triple option is an American football play used to offer several ways to move the football forward on the field of play. The triple option is based on the option run, but uses three players who might run with the ball instead of the two used in a standard option run.
In American football, a play is a close-to-the-ground plan of action or strategy used to move the ball down the field. A play begins at either the snap from the center or at kickoff. Most commonly, plays occur at the snap during a down. These plays range from basic to very intricate. Football players keep a record of these plays in a playbook.
On defense in American football, a pass rush is charging across the line of scrimmage towards the quarterback in an effort to stop or "sack" them. The purpose is tackling, hurrying or flushing the quarterback out of their protective pocket or the play's design.
In American football, the 3–4 defense is a common defensive alignment consisting of three down linemen and four linebackers. It is a called a "base defense" because it is the default defensive alignment used on "base downs". However, defenses will readily switch to other defensive alignments as circumstances change. Alternatively, some defenses use a 4–3 defense.
In American football, a 4–3 defense is a defensive alignment consisting of four down linemen and three linebackers. It is called a "base defense" because it is the default defensive alignment used on "base downs". However, defenses will readily switch to other defensive alignments as circumstances change. Alternatively, some defenses use a 3–4 defense.
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.
A defensive tackle (DT) is a position in American football that will typically line up on the line of scrimmage, opposite one of the offensive guards, however he may also line up opposite one of the tackles. Defensive tackles are typically the largest and strongest of the defensive players. Depending on a team's individual defensive scheme, a defensive tackle may be called upon to fill several different roles. These roles may include merely holding the point of attack by refusing to be moved, or penetrating a certain gap between offensive linemen to break up a play in the opponent's backfield. If a defensive tackle reads a pass play, his primary responsibility is to pursue the quarterback, or simply knock the pass down at the line if it is within arm's reach. Other responsibilities of the defensive tackle may be to pursue the screen pass or drop into coverage in a zone blitz scheme. In a traditional 4–3 defense, there is no nose tackle. Instead there is a left and right defensive tackle. Some teams, especially in the National Football League (NFL), have a nose tackle in this scheme, but most of them do not.