AFC champion Pittsburgh, in its initial Super Bowl appearance, and NFC champion Minnesota, making a third bid for its first Super Bowl title, struggled through a first half in which the only score was produced by the Steelers' defense when Dwight White downed Vikings' quarterback Fran Tarkenton in the end zone for a safety 7:49 into the second period.
The Steelers forced another break and took advantage on the second-half kickoff when Minnesota's Bill Brown fumbled and Marv Kellum recovered for Pittsburgh on the Vikings' 30.
After Rocky Bleier failed to gain on first down, Franco Harris carried three consecutive times for 24 yards, a loss of three, and a 9-yard touchdown and a 9-0 lead.
Though its offense was completely stymied by Pittsburgh's defense, Minnesota managed to move into a threatening position after 4:27 of the final period when Matt Blair blocked Bobby Walden's punt and Terry Brown recovered the ball in the end zone for a touchdown.
Fred Cox's kick failed and the Steelers led 9-6. Pittsburgh wasted no time putting the victory away.
The Steelers took the ensuing kickoff and marched 66 yards in 11 plays, climaxed by Terry Bradshaw's 4-yard scoring pass to Larry Brown with 3:31 left.
Pittsburgh's defense permitted Minnesota only 119 yards total offense, including a Super Bowl low of 17 rushing yards.
The Steelers, meanwhile, gained 333 yards, including Harris's record 158 yards on 34 carries.