James Franklin passed for 303 yards and three touchdowns, while Dorial Green-Beckham hauled in six passes for 144 yards and a couple of scores. Missouri piled up 534 yards -- the teams combined for 1,211 yards in a conference supposedly known for defense -- but it wasn't nearly enough against Auburn's hurry-up spread.
Coming into the game, Missouri was one of the top teams in the nation against the run and ranked second in the SEC behind Alabama. The most yards they had given up on the ground was 184 the previous week in a victory over 2012 Heisman Trophy winner Johnny Manziel and Texas A&M.
Mason had more yards than that in the first half, putting up 195 by the time he trotted to the locker room and just 6 yards off the SEC championship game record. He broke the mark set by LSU's Justin Vincent in 2003 on the second play of the second half -- and kept right on going from there.
"I've never had holes that big to run through," Mason said, crediting the guys in the trenches. "No one expected 300 yards. I didn't expect it."
Quarterback Nick Marshall shook off two early fumbles, one of which Missouri returned for a touchdown. He ran for 101 yards and a touchdown and passed for 132 yards and another score.
The lead changed hands seven times. Missouri's last gasp was Franklin's 5-yard touchdown run, followed by a two-point conversion, that closed the gap to 45-42 heading to the final period. But Auburn dominated the final 15 minutes behind the play of Mason.
Late in the game, when Auburn had finally wrapped it up, Mason got a hug on the sideline from Auburn's greatest back, Bo Jackson.
"He's one of the better players ever to wear an Auburn helmet," Malzahn said, referring to Mason, not Bo.
"Thanks, coach," Mason said.
Information from The Associated Press was used in this report.