Pittsburgh Steelers safety Mike Wagner (23) tackles Dallas Cowboys Hall of Fame quarterback Roger Staubach (12) during Super Bowl X Jan. 18, 1976, at the Orange Bowl in Miami. (Tony Tomsic via AP)

Fans react as Lynn Swann of the Pittsburgh Steelers holds the ball high after scoring on a pass from Terry Bradshaw in the fourth period of Super Bowl X. The Steelers beat the Dallas Cowboys 21-17 at the Orange Bowl Jan.19,1976. (AP Photo/Joe Caneva)

Dallas Cowboys quarterback Roger Staubach scrambles to get away from Pittsburgh Steelers Dwight White (78) on Jan. 19,1976 during the second quarter of Super Bowl X at the Orange Bowl in Miami. (AP Photo/Joe Caneva)

Dallas Cowboys quarterback Roger Staubach looks for an open receiver during Super Bowl X on Jan. 18, 1976 in Miami against the Pittsburgh Steelers. (Associated Press)

Pittsburgh Steelers Lynn Swann dives as he catches a pass from quarterback Terry Bradshaw during Super Bowl X in Miami, Fla., on Sunday, Jan. 18, 1976. (Associated Press)

Players take the field for workouts about an hour before the start of the Super Bowl game between the Pittsburgh Steelers and the Dallas Cowboys at the Orange Bowl in Miami, Jan. 18, 1975. (AP Photo/Bill Hudson)

Pittsburgh Steelers Hall of Fame wide receiver John Stallworth (82) is tackled as he catches a pass during Super Bowl X Jan. 18, 1976, at the Orange Bowl in Miami. (Tony Tomsic via AP)

Dallas Cowboys quarterback Roger Staubach (12) hands off to fullback Robert Newhouse (44) in Super Bowl X against the Pittsburgh Steelers at the Orange Bowl in Miami, Florida on January 18, 1976. (AP Photo/Vernon Biever)

NFL Commissioner Pete Rozelle presents the Super Bowl trophy to Pittsburgh Steelers president Dan Rooney and head coach Chuck Noll after Steelers defeated the Dallas Cowboys, 21-17, to win Super Bowl X in the Orange Bowl in Miami, Jan. 18, 1976. (AP Photo/Harry Cabluck)

Running back Franco Harris of the Pittsburgh Steelers runs upfied in a 21-17 win over the Dallas Cowboys in Super Bowl X on January 18, 1976 at the Orange Bowl in Miami, Florida. (AP Photo/Vernon Biever)

The NFL Super Bowl X Most Valuable Player watch created for Pittsburgh Steelers wide receiver Lynn Swann (88) is photographed on April 1, 1986 in New York. (AP Photo/Paul Spinelli)

A detail view of the Super Bowl X ticket is seen for a game between the Dallas Cowboys and the Pittsburgh Steelers in Miami on Jan. 18, 1976. (National Football League)

Pro Football Hall of Fame and Pittsburgh Steelers quarterback Terry Bradshaw (12) throws the ball downfield in the Steelers 21-17 victory over the Cowboys in Super Bowl X on January 18, 1976 at the Orange Bowl in Miami, Florida. (National Football League)

Pro Football Hall of Fame and Pittsburgh Steelers wide receiver Lynn Swann (88) makes a diving catch over Dallas Cowboys defensive back Mark Washington (46) in the Steelers 21-17 victory over the Cowboys in Super Bowl X on January 18, 1976 at the Orange Bowl. (National Football League)

Pittsburgh Steelers wide receiver Lynn Swann goes up to make a catch over Dallas Cowboys cornerback Mark Washington in the Steelers 21-17 win over the Cowboys in Super Bowl X on January 18, 1976 at the Orange Bowl in Miami, Florida. (National Football League)

Pittsburgh quarterback Terry Bradshaw turns to hand off to running back Rocky Bleier in the Steelers 21-17 win over the Cowboys in Super Bowl X on January 18, 1976 at the Orange Bowl in Miami, Florida. (National Football League)

The Vince Lombardi trophy for the Super Bowl X game of the Pittsburgh Steelers vs the Dallas Cowboys at the Orange Bowl in Miami, Florida on January 18, 1976. Super Bowl X - Dallas Cowboys vs Pittsburgh Steelers - January 18, 1976 (Associated Press)

A detail view of a Pittsburgh Steelers Super Bowl X ring is seen in 1975. (National Football League)