If the Allstate Sugar Bowl was defined by the performance of a quarterback, it wasn't the storybook ending to Alabama quarterback AJ McCarron's career. It was the emergence of Oklahoma quarterback Trevor Knight.

Oklahoma upset the Alabama Crimson Tide 45-31 thanks to a 348-yard, four-touchdown performance by Knight, who called the game "a dream come true." It was the second straight night that a double-digit underdog won a BCS game outright.

Entering the game, Oklahoma coach Bob Stoops declined to name a starting quarterback. Knight had been injured against Oklahoma State and Blake Bell, his backup, had led the Sooners to a win in the final seconds. And you couldn't help but wonder how the evening would go for the redshirt freshman after he threw an interception on Oklahoma's first drive.

The answer: Almost impeccably.

Knight got some help -- the Oklahoma defense picked off McCarron twice in the first half and recovered an Alabama self-inflicted fumble -- but he capitalized on big plays to his receivers following the first two turnovers. The first was a 45-yard pass to Lacoltan Bester. The second was a 43-yarder to Jalen Saunders. The 31-17 deficit that Alabama faced at halftime was ultimately insurmountable.

Help from the Oklahoma defense didn't come only from the turnovers, it also came from pressure on McCarron. Alabama had given up 10 sacks all season entering Thursday night's game, but Oklahoma's defense blitzed McCarron and the Tide offensive line for seven sacks, including on what ended up being McCarron's final play from scrimmage as a member of the Crimson Tide.

Trailing 38-31, McCarron and the offense got the ball back with 56 seconds left at the Alabama 18-yard line. But on the first play of the drive, linebacker Eric Striker sped around the left side to strip-sack McCarron while led to Geneo Grissom picking up the ball and diving into the end zone.

After the ensuing squib kickoff bounced off an Alabama player and was recovered by Oklahoma, McCarron's fourth career loss was official. He leaves Alabama with a career record of 36-4, two national championships as a starter, and his name etched all over Alabama's passing records. Though somewhat ironically, the man whose Alabama career has been defined by the term "winner," ends as a loser.

Because of that, it could be a massive boost for the Sooners, who will likely enter as Big 12 favorites once again. The strong performance of a young quarterback will do that, as will a defense that had just two seniors atop the depth chart entering the game.

“[Knight] lit it up," Stoops said. "He took care of the football, made great throws and was competitive. He showed everybody what we’ve been seeing for a couple of years. He has a chance to be really special.”

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Nick Bromberg

is the assistant editor of Dr. Saturday on Yahoo Sports. Have a tip? Email him at nickbromberg@yahoo.com or follow him on Twitter!
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