5–2 defense

In American football, the 5–2 defense is a defensive alignment consisting of five down linemen and two linebackers.

Historically, there are two significant variations of the 5–2 defense in professional and college football. The first is the defense created by Earle (Greasy) Neale. This defense was prominent in the National Football League from the late 1940s through the middle 1950s and was a precursor defense to Buddy Ryan's 46 defense.Paul Brown describes the defense as having a tight five man line, and linebackers who were to jam offensive ends as they came off the line. Brown goes on to say that the use of four defensive backs was innovative at the time. By 1950, the base defense of NFL teams were five man line defenses, either the 5–2 Eagle or the 5–3–3.

The 5–2 Eagle has a (passing) hole in the middle of the defense, usually dealt with by having outside linebackers jam the ends. Offenses countered by using slot backs instead of tight ends. Consequently, teams began to experiment, around 1954, with pulling the middle guard back a couple yards and putting him in a 2-point stance. The success of the New York Giants in 1956 with their base 4–3 lead to a rapid conversion to the 4–3 in 1957. Almost all teams switched to the new defense at that time.

Note that in this defense, if you pull the middle guard and replace him with a middle linebacker, you get to an early version of the 4-3 defense. Conversely, if you take a 4–3 defense and replace the middle linebacker with a middle guard, then you convert a 4–3 into a 5–2 Eagle. This latter switch is historically significant in at least one game. In 1971, George Allen pulled his middle linebacker, replacing him with defensive lineman Manny Sistrunk, defeating Green Bay in a playoff game with his unexpected five man front, shutting down the Packers' powerful rushing combination of John Brockington and MacArthur Lane.

The second is the 5–2 that Bud Wilkinson developed while a head coach at Oklahoma. The latter defense, also called the Oklahoma, is supposed to have arisen from Bud's exposure to Earle Neale's 5–2 in a College All Star game after the Philadelphia Eagles' first championship. Bud took the defense back with him to Oklahoma and adapted lineman and linebacker positions to better handle the college offenses of the time. In particular, the split between the middle guard, or nose tackle, and the other defensive tackles grew wider in the Oklahoma, and the linebackers were positioned a couple yards behind the line, and facing the opponent's offensive guards.

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