Coach Bud Wilkinson—who, at Oklahoma in the 1940s, is credited with installing the first 3--4 system, in order to force RBs inside—wins his first national championship, with the Sooners, to be followed by titles in '55 (above) and '56.
After injuries to Dolphins DE Jim Riley and DT Bob Heinz, coach Don Shula deploys the 3--4. Miami's No-Name D, led by the likes of Bill Stanfill, allows the NFL's fewest points and yards en route to a 14--0 season, including the first Super Bowl win for a 3--4 team. Miami repeats in '73.
Patriots coach Chuck Fairbanks—who, like Wilkinson, coached at OU—popularizes the 3--4 in the NFL with a new two-gap tweak. By the 1980s, that defense is the league's preferred alignment.
After four Super Bowl wins in six years with the 4--3 Steel Curtain, Pittsburgh's Chuck Noll switches to the 3--4 due to retiring personnel (Dwight White, Joe Greene, L.C. Greenwood). The Steelers reach 10 wins only once more in the next decade.
Five years after Bill Parcells takes over as Giants coordinator and switches New York from a 4--3 to a 3--4, OLB Lawrence Taylor has one of the best defensive years ever: 20½ sacks for a Super Bowl champion. In 1990 he bags 10½ in another Lombardi-lifting campaign.
Jimmy Johnson brings his 4--3 D from Miami (where he won the 1987 national championship) to the Cowboys and leads America's Team to Super Bowl wins in '93 and '94. The pendulum swings, and by 2001 the 3--4 is almost extinct; only Pittsburgh and New England run it.
Popularity be damned: The Steelers allow the fewest yards in the NFL and, along with the Patriots, rank in the top six in fewest points allowed. At season's end New England (with OLB Mike Vrabel) wins the first of its three Super Bowls.
The 3--4 is making a resurgence, thanks largely to the abundance of pass-heavy offenses. Almost half of the NFL will run a 3--4 base this season.
EARL SHUGARS/AP (WILKINSON)
NFL PHOTOS/AP (STANFILL)
JOHN BIEVER FOR SPORTS ILLUSTRATED (TAYLOR)
DAMIAN STROHMEYER FOR SPORTS ILLUSTRATED (JOHNSON)
AMY SANCETTA/AP (VRABEL)