After World War II, the 5-3 defense was the major defense used. This defense was carried over from prewar years. However, it became clear by 1948 that the linebackers were being forced to cover fast halfbacks off the T formation. Greasy Neale, coach of the Philadelphia Eagles, came up with the idea of the "Eagle Defense," which utilized four defensive backs covering two fast halfbacks and two fast ends, the problem was solved.
Two things happened offensively which eliminated the Eagle Defense as the best defense against the pro "T." First, the pass offense became very effective became of the lack of pass defensive strength over the middle. All an offensive coach would have to do to eliminate all linebackers would be to swing backs wide.
The result was that the defense lacked strength in the middle area. To alleviate this weakness coaches began to fill this area with another man.
This formation, then, appeared to be the solution. However, the sweeping success of the "Split T" in college effected another major change in the early Fifties and led to the downfall of the Eagle Defense. With the introduction of the split line the middle guard found himself virtually isolated.
As the offensive play began the middle guard would "holler" for help. The only ones to help were the tackles, so they closed down on the offensive guards. Now the outside linebacker was isolated. A typical result is shown below.
Eagle Defense could not stop running game with a split line. Now the defensive coaches had to turn to the only solution to their problem, a defense that would solve the two weakness of the Eagle Defense. The present 4-3 defense answered both needs. Here was the blending of two defenses into one: the Eagle Defense of Greasy Neale’s Philadelphia team and the 6-1 "Giants Umbrella" devised by Steve Owen. The following the series of diagrams show step by step the evolution of the two defenses with the 4-3 defense resulting. This should be with us for some time-the linebackers are the key.
Giant coach Steve Owen picked up valuable personnel when the American Conference disbanded in 1950 and used these men to form his "Umbrella Defense," which was specifically designed to stop the new Cleveland Browns.
I don’t believe that there is any question of the tremendous appeal of defensive football today. Back in 1950, when Owen’s famed "Umbrella Defense" stopped the powerful Cleveland Browns, 6-0, the average fan could pass this feat off as "an off-day for the Browns." Today, you can think back over the last ten years to the one constant factor in championship teams—defense! The Philadelphia Eagles of the late Forties, the Baltimore Colts and the New York Giants of the late Fifties were all defensive powers.
The tactical changes in the game are devised by the coaches—the ingenious generals of football-and are in most cases the result of the interactions in the offensive and the defensive strategies of the various teams in the league. Below are diagrams of the three key offensive changes in the decade.
1953: IN 1953 teams began using more spread formations and the slot-back was introduced to combat the 6-1 umbrella defense. This loosened the 6-1 up and gave offenses greater passing areas.
1956: Teams found, with the waning of the 6-1 and the more constant use of the 4-3, that they were now able to cover the spread and slot-back formation more adequately. Coaches felt, however, the offenses had to present a stronger blocking picture for the running game, and this resulted in the off-side end always spread and the end on flanker side closed for greater running strength.
1959: Al Sherman and other offensive coaches were of the opinion that teams were beginning to leave the basic 4-3 a little and play defensive men in "gaps"—to destroy stronger blocking created by the closed end and add defensive strength closest to strength of play (strong side). Perhaps offensively now there will be another trend to try combat these "gap" defense.