5-3 defense

In American football, the 5–3 defense is a defensive alignment consisting of five down linemen and three linebackers.

Defense is based on two standard formations, the 6-2-3, and the 5-3-3. All else is "variations."

The 5-3 is a defense that appeared in the 1930s due to the demands of the ever improving passing attacks of the time, as well as innovations in the T formation (in 1933, pro football's passing rules were liberalized). One origin story is that of Steve Owen, coach of the New York Giants. He says he invented it to surprise the Bears in 1933. He then goes on to say that the 5-3 was in part responsible for the division championships won by the Giants in 1933, 1934, and 1935.

By the late 1930s, the two standard defenses in college and the NFL were the 6-2 and the 5-3. The 5-3 was regarded as a pass defense, the 6-2 the run defense. The usage of the 5–3 defense accelerated as the T formation became more popular and more effective.Dana Bible, in his 1947 coaching tome, called it the best defense against the T formation. By 1950, the base defenses in the NFL were all five man line defenses, either the 5-3 or the 5-2 Eagle.

Three teams known for their use of the 5-3-3 were the Cleveland Browns, the Pittsburgh Steelers, and the San Francisco 49ers.Paul Brown attributed his loss in the 1951 NFL Championship, in part, to an error in coverage in their three man backfield. By the later 1950s, the 5-3 had died out in the NFL, replaced by the 5-2 Eagle or the 4-3.Hardy Brown, a 5-3 middle linebacker for the 49ers, and one of the hardest hitting linebackers of his era, was unable to adapt to changing times, and was cut because he could not deal with the demands of the new 4-3 defense.

Colleges tend to have less powerful passing games than professional football, and the use of three man backfields or an overshifted secondary is common practice. In the overshift, one of the safeties plays a monster or rover role, often moving to the strong side of the offensive formation to about linebacker depth. As a consequence, a body of defenses has emerged that have 5 man lines, 2 linebackers and a monster or rover back. This rover is a hybrid player, expected to use a linebacker technique when runs are encountered, and act like a pass defender otherwise.

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