Defensive tackle

Defensive tackle (DT) is a position on the field in American and Canadian football.Defensive Tackles are typically the largest and strongest of the defensive players. The defensive tackle typically lines up opposite outside shoulder of the offensive guards. 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, which also prevents offensive lineman from being able to get to the linebackers and successfully block them on running plays or penetrating a certain gap between offensive linemen to break up a play in the opponent's backfield. The former is often referred to as "two gap" play, the latter as "one gap" play. Historically, one gap play was more frequently the role common for a defensive tackle to use as two gap play requires a defensive tackle to be rather large (most DTs who are good at two gap play are over 330 pounds) a development that has only occurred in the last 5-10 years of football. The concept of using one or both defensive tackles in "two gap" play was popularized on the 2000 Baltimore Ravens, who used Sam Adams and Tony Siragusa in this role, allowing their linebackers (namely Ray Lewis) to attack the ball carrier without being blocked by an offensive player. 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's 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.
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