In gridiron football, defensive backs (DBs), also called the secondary, are the players on the defensive side of the ball who play farthest back from the line of scrimmage. They are distinguished from the other two sets of defensive players, the defensive linemen who play directly on the line of scrimmage, and the linebackers, who play in the middle of the defense, between the defensive line and the defensive backs.
Linebacker (LB) is a playing position in gridiron football. Linebackers are members of the defensive team, and line up three to five yards behind the line of scrimmage and the defensive linemen. They are the "middle ground" of defenders, playing closer to the line of scrimmage than the defensive backs (secondary), but farther back than the defensive linemen.
In gridiron football, blitzing is a tactic used by the defense to disrupt pass attempts by the offense. During a blitz, a higher than usual number of defensive players will rush the opposing quarterback, in an attempt either to tackle them or force them to hurry their pass attempt.
Strategy is a major part of American football.
American football positions have slowly evolved over the history of the sport. From its origins in early rugby football to the modern game, the names and roles of various positions have changed greatly, some positions no longer exist, and others have been created to fill new roles.
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 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.
In sports, a starting lineup is an official list of the set of players who will participate in the event when the game begins. The players in the starting lineup are commonly referred to as starters, whereas the others are substitutes or bench players.
In American football, a dimeback is a cornerback or safety who serves as the sixth defensive back on defense. The third cornerback or safety on defense is known as a nickelback. The dimeback position is essentially relegated to backup cornerbacks and safeties who do not play starting cornerback or safety positions. Dimebacks are usually fast players because they must be able to keep up on passing plays with 3+ wide receivers.
In American football, a nickelback is a cornerback or safety who serves as the additional defensive back in a nickel defense. A base defense consists of two cornerbacks and two safeties, making the nickelback the fifth defensive back on the field, thus tying the name of the position to the name of the North American 5-cent piece.
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 "special teams". Within these three separate "platoons", various positions exist depending on the jobs that the players are doing.
In American football, a nickel defense is any defensive alignment that uses five defensive backs, of whom the fifth is known as a nickelback. The original and most common form of the nickel defense features four down linemen and two linebackers. Because the traditional 4–2 form preserves the defense's ability to stop an opponent's running game, it has remained more popular than its variants, to the extent that even when another formation technically falls within the "nickel" definition, coaches and analysts will refer to it by a more specific designation that conveys more information with equal or greater conciseness.
The New England Patriots generally run a modified Erhardt-Perkins offensive system and a Fairbanks-Bullough 3–4 defensive system, though they have also used a 4–3 defense and increased their use of the nickel defense.
The prevent defense is a defensive alignment in American football that seeks to prevent the offense from completing a long pass or scoring a touchdown in a single play and seeks to run out the clock, at the expense of allowing short-yardage gains. It is used by a defense that is winning by more than a touchdown, late in the fourth quarter, or in specific situations, such as third-and-very-long if it seems clear that the offense must pass the football to gain long yardage.
In American football, the 3–4 defense is a common defensive alignment consisting of three down linemen and four linebackers. It is called a "base defense" because it will readily switch to other defensive alignments as circumstances change. Alternatively, some defenses use a 4–3 defense: four down linemen and three linebackers.
Zone coverage is a defense scheme in gridiron football used to protect against the pass.
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.
The 7–1–2–1, or seven-diamond defense, used seven "down linemen", or players on the line of scrimmage at the time of the snap, one linebacker, two safeties relatively close to the line and one safety farther downfield. The formation was created by Minnesota Golden Gophers coach Henry L. Williams in 1903, reputedly to stop Michigan back Willie Heston. By some accounts in the mid-1930s, the 7–1–2–1 was considered "almost obsolete" due to its weakness against the forward pass, whereas the 7–2–2 defense was still considered viable. Yet Bill Arnsparger notes the use of the seven-diamond from the 1940s into the 1960s, as a defensive adjustment to the common wide tackle 6 defenses of the time. Further, the form of the 7 diamond as derived from a wide tackle 6, with a more compact line spacing than the 1930s era 7 man lines, shows a marked similarity to the 46 defense of Buddy Ryan.
