Baltimore Colts kicker Jim O'Brien (80) leaps after kicking the winning field goal against the Dallas Cowboys with five seconds left in the game, as the Colts beat the Cowboys 16-13 in Super Bowl V, Jan. 17, 1971, in Miami. At right is backup quarterback Earl Morrall (15), who replaced injured starter Johnny Unitas. Morrall held the ball for O'Brien's kick. (Associated Press)

Jim O'Brien (80) kicks the game winning goal for the Baltimore Colts over the Dallas Cowboys in Super Bowl V action for the NFL championship in Miami, Fla., Jan. 17, 1971. Earl Morrall (15) held the ball. (Associated Press)

Baltimore Colts defensive end Bubba Smith (78) receives congratulations as he leaves the field following Super Bowl V, a 16-13 victory over the Dallas Cowboys on January 17, 1971, at the Orange Bowl in Miami, Florida. (AP Photo/Vernon Biever)

Pro Football Hall of Fame and Dallas Cowboys defensive back Mel Renfro (20) sitting on the bench in disappointment in the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Baltimore Colts running back Tom Nowatzke (34) runs upfield against the Dallas Cowboys during Super Bowl V in Miami, Fla., Jan. 17, 1971. The Colts defeated the Cowboys, 16-13. (National Football League)

Baltimore Colts quarterback Earl Morrall (15) throws a pass during the Colts 16-13 victory over the Dallas Cowboys in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Hall of Fame head coach Tom Landry of the Dallas Cowboys grimaces after a call goes against his team during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys quarterback Craig Morton (14) hands off during Super Bowl V, a 16-13 loss to the Baltimore Colts on January 17, 1971, at the Orange Bowl in Miami, Florida. (National Football League)

Baltimore Colts Hall of Fame quarterback Johnny Unitas (19) fires a pass with Dallas Cowboys defensive end Larry Cole (63) in his face during Super Bowl V, a 16-13 Colts victory on January 17, 1971, at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys left tackle Ralph Neely (73) gets in blocking position during Super Bowl V, a 16-13 loss to the Baltimore Colts on January 17, 1971, at the Orange Bowl in Miami, Florida. (National Football League)

Super Bowl V Program cover between the Baltimore Colts vs Dallas Cowboys to be played on January 17, 1971. (National Football League)

Baltimore Colts running back James Duncan finds a hole to carry through in a 16-13 win over the Dallas Cowboys in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys linebacker Chuck Howley in action in 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Baltimore Colts Hall of Fame quarterback John Unitas completed three of nine passes for 88 yards and a touchdown in the Colts 16-13 win over the Dallas Cowboys in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys Hall of Fame cornerback Mel Renfro (20) brings down Baltimore Colts wide receiver Ed Hinton (33) as receiver Roy Jefferson (87) moves to block leaping Hall-of-Fame cornerback Herb Adderley (26) during Super Bowl V, a 16-13 Colts victory on January 17, 1971, at the Orange Bowl in Miami, Florida. (AP Photo/Vernon Biever)

Baltimore Colts running back Tom Nowatzke (34) runs upfield against the Dallas Cowboys during Super Bowl V in Miami, Fla., Jan. 17, 1971. The Colts defeated the Cowboys, 16-13. (National Football League)

Baltimore Colts quarterback Earl Morrall (15) throws a pass during the Colts 16-13 victory over the Dallas Cowboys in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Baltimore Colts running back Tom Nowatzke (34) carries the football during the Colts 16-13 victory over the Dallas Cowboys in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys linebacker Chuck Howley (54) runs with the football after intercepting a pass during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. Howley had two interceptions. (National Football League)

Dallas Cowboys running back Walt Garrison (32) carries the football before being stopped by Colts linebacker Mike Curtis during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys quarterback Craig Morton (14) sets up to pass during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys running back Duane Thomas (33) carries the football and is stopped by Colts linebacker Mike Curtis (32) during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys quarterback Craig Morton (14) looks to handoff during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys quarterback Craig Morton (14) drops back to pass during the Cowboys 16-13 loss to the Baltimore Colts in Super Bowl V on January 17, 1971 at the Orange Bowl in Miami, Florida. (National Football League)

Dallas Cowboys running back Duane Thomas (33) follows guard Blaine Nye (61) during Super Bowl V, a 16-13 loss to the Baltimore Colts on January 17, 1971, at the Orange Bowl in Miami, Florida. (National Football League)