Let's start with a quick quiz; match each QB with his career stats:
GP Comp PCT Yds Y/A TD INT
#1 168 51.9 27989 7.2 212 210
#2 246 57.0 47003 7.3 342 266
Of course, #2 is Fran Tarkenton, and #1 is Terry Bradshaw. Tarkenton threw for over 2500 yards 14 times, 13 of them coming in 14 game seasons. Bradshaw did that just 4 times - and needed more than 14 games in all but once. Bradshaw's injuries in 1974 and 1983 weaken his overall statistics and shorten his career, especially compared with Tarkenton, who was something of an iron man, missing just 2 games over his first 16 seasons. One or both of these QBs played in 6 out of the 7 Super Bowls from 1974 to 1980.
The knock on Tarkenton was summarized by his first coach, Norm Van Brocklin, who once said, "He will win games he should lose, and lose games he should win, but he will never win the games he has to win" (The Super Bowl, 1990, pg. 144). Tarkenton was playing with the Giants as Joe Kapp led the Vikings to a Super Bowl defeat in SB IV, but he had returned for the 1972 season. The next year, the Vikings lost to the defending champion Dolphins 24-7 in SB VIII. Tarkenton was mediocre in the game (182 yards, no TDs, one INT), but he had little help from his running game (72 yards) while the Dolphins ran for 196 yards and passed for just 73.
In Super Bowl IX, it looked like Terry Bradshaw and the Steelers stole the Dolphins playbook. Bradshaw was just 9-of-14 for 96 yards and one TD, but Pittsburgh gained 249 yards on the ground, including 158 by Super Bowl MVP Franco Harris. Tarkenton was awful, completing only 11 of 26 passes, and was intercepted 3 times, including one at the goal line late in the first half with the score 2-0 Pittsburgh. For the second straight year, Tarkenton and the Vikings never led in the game and lost again, 16-6.
Pittsburgh played Dallas the following season, and Bradshaw outplayed Roger Staubach in a 21-17 win that wasn't secured until a last second interception in the end zone. Although Bradshaw had thrown for more yards than the Steelers ground game had gained (209 to 149), Pittsburgh was still viewed as a defensive team with a great running game. The MVP had gone to Lynn Swann, who caught a 64 yard touchdown from Bradshaw and finished with 161 yards on just 4 catches. No one considered Bradshaw one of the all-time greats yet.
Tarkenton got his last shot at a super Bowl ring the following season. The Oakland Raiders had defeated the Steelers in the AFC Championship game, and had overcome their own history of frustration, having lost 6 AFL or AFC Championship games in a row since reaching Super Bowl II (The Super Bowl, 1990, pg. 185). But once again, the Vikings were overmatched on the ground (266-71) and it took a toll on Tarkenton and the passing game. Tarkenton threw two interceptions in the fourth quarter, but it was already 19-7 at that point, and when his second pick was returned 75 yards for a touchdown, Oakland had its 32-14 margin of victory. You also can't blame Tarkenton for the turning point of the game. Late in the first quarter, Minnesota blocked Ray Guy's punt and recovered at the Oakland three yard line. But two plays later, Brent McClanahan fumbled and the Raiders got the ball back. Thirteen plays later, Oakland took a 3-0 lead, then their defense forced Minnesota to go three-and-out on their next two possessions while Oakland's offense scored two touchdowns to take a commanding 16-0 lead in the second quarter.
That was it for the Vikings, but the Steelers were just getting started. Terry Bradshaw built his legend in Super Bowls XIII and XIV, throwing for over 300 yards in each game and winning both MVP awards. The Steelers had become a passing team, with Bradshaw setting career highs in TD passes (28 and 26) in the 1978 and 1979 regular seasons. Franco Harris played a supporting role in both games, as the Steelers defeated the Cowboys 35-31 and the Rams 31-19 (the latter game made close only by Bradshaw's three interceptions).
For Bradshaw, the four wins could not have been more different. In the first two he was almost an after-thought, spending most of his time handing off to Franco Harris. But in the last two, he was the gun-slinger who led his team to victory in high-scoring games.
By comparison, Tarkenton never had a good enough supporting cast around him. In all three of his Super Bowls, his teams were out gained, and the rushing edge was decisive:
SB Opp Minn
VIII 196 72
IX 249 17
XI 266 71
If Tarkenton had Harris or the Dolphins Larry Csonka, along with those teams' outstanding run-blockers, Minnesota might have won a title or two. But there's no denying that Bradshaw came up big when it counted.
QB Super Bowls Won (or Lost)
Bradshaw 9, 10, 13, 14
Tarkenton 8, 9, 11
Note: MVP in bold
Note on References: All statistics taken from Pro Football Reference. Other details taken from The Super Bowl: Celebrating a Quarter-Century of America's Greatest Game, published in 1990 by the NFL and Simon & Schuster. The book includes play-by-play for the first 24 Super Bowls.