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Positions

The players on defense may arrange themselves in any manner, as long as all players are "behind the line" (that is, on the side of the line nearest their own end zone). Players who line up opposite the offensive line are called defensive linemen, usually with one or two defensive tackles in the middle (a single defensive tackle is often called the nose guard or nose tackle) and with one defensive end on each side. A defensive lineman's job is typically to put pressure on the opposing team's quarterback by rushing the offensive line. The defensive line is also most often the first set of players the opponent must get through should they choose to run the ball. Behind the linemen are the linebackers. A linebacker's job can be any number of things, including trying to rush the opposing team's quarterback, stopping the opponents running back on run plays, or covering the opponent's tight end or wide receivers. Positioned opposite the wide receivers are the cornerbacks. Their primary responsibility is to cover the wide receivers. Farthest back from the line are the safeties, usually in the middle of the field behind the linebackers. The safeties are the last line of defense against the opponent. Like a linebacker, a safety's role can vary, however, their most common role is to help the cornerbacks cover the opponent's wide receivers, which is called "double coverage". The linemen and linebackers close to the line of scrimmage, are often referred to as playing "in the box". Players outside "the box" (usually cornerbacks and safeties) are collectively referred to as the "secondary".