The NFL represents a constant battle of schemes and concepts between offenses and defenses. The third receiver predicated the 4-3 defense in the 1950s. The AFL’s vertical multi-receiver sets caused the creation of the 53 defense in the 1960s. The West Coast offense forced the advancement of the zone blitz in the 1980s. The 49 defense killed the old two-back pro set.
Throughout pro football history, there have always been those base, tentpole schemes that defined the game, because they worked so well… at least, until somebody came along with the perfect answers to erase them.
