Brown ran for three second-half touchdowns, Curtis Lofton returned a fumble for a score and the No. 6 Sooners knocked No. 11 Missouri from the ranks of the unbeaten with a 41-31 victory Saturday night.
"The fourth quarter, that's all we preach around here," said Brown, Oklahoma's third-leading rusher behind DeMarco Murray and Allen Patrick. "The difference from this year and last year, we're more of a fourth quarter team. We can go the distance and get the job done."
Brown put the Sooners (6-1, 2-1 Big 12) ahead to stay with his 1-yard touchdown run with 12:26 remaining, and Lofton scooped up a botched handoff and returned it 15 yards for a score 46 seconds later as Oklahoma kept the Tigers from entering the national title picture.
Brown, who finished with 67 yards on 13 carries, sealed the win with a 23-yard TD run with 2:39 remaining.
"I thought Chris Brown was sensational in the fourth quarter," Sooners coach Bob Stoops said. "Everybody has their opinions on who should be playing. I think Chris showed tonight why he deserves his snaps as well."
Missouri (5-1, 1-1) had lost 16 straight games in Norman dating back to 1966, but put up a fight in this one.
Quarterback Chase Daniel, who ranks third in the nation in total offense with a 380-yard average, was equally good as a setup man for the Tigers. He delivered key blocks on both touchdown runs by NCAA all-purpose yardage leader Jeremy Maclin, and then pitched the ball to Jimmy Jackson on a 4-yard option run that put Missouri up 24-23 late in the third quarter.
After that, Brown and Oklahoma's running game -- which had totaled only 40 yards in the first three quarters -- took over. Brown finished the ensuing drive with three rushes for 23 yards and the go-ahead score.
"It just shows a lot about our offensive linemen and our running backs. It just shows that they're willing to go after it for four quarters," said Oklahoma quarterback Sam Bradford, who came in as the nation's top-rated passer. "I think eventually we may have wore them down a little bit just getting after them, and it just got going in the fourth quarter."
Daniel botched a handoff to Maclin on Missouri's second play from scrimmage after Brown's score, and it resulted in disaster for the Tigers, looking for their fifth 6-0 start in school history.
"It was just a mix-up," Daniel said. "We can't make those costly turnovers."
Missouri's next drive fizzled after a 5-yard loss on a reverse and the second sack of the game by Auston English -- the Big 12's sack leader -- and Daniel threw his second interception of the game to wash away any remaining hope.
"In big games like this, generally the team that makes the fewest mistakes is going to win, and that's what happened," Tigers coach Gary Pinkel said. "With games of this magnitude, mistakes are generally going to dictate how the game is going to come out."
Daniel still threw for more than 300 yards for the eighth time in his last nine games. He finished with 361 yards on 37-for-47 passing with his only touchdown coming on a 5-yard toss to Martin Rucker with 12 seconds remaining.
The Tigers, who'd had at least 195 yards rushing in their previous four games, managed only 57 with starting running back Tony Temple sidelined by a sprained ankle.
Instead, the Sooners were able to get their ground game going first after Brown finally got in the mix. And who knows how high they'll climb after losses by top-ranked LSU and No. 2 California?
"We know we've got to win every week. We can't worry about what someone else is doing. We've got to worry about winning," Brown said.
Bradford completed 24-of-34 passes for 266 yards and two touchdowns for Oklahoma, which won its 15th straight home game.
A series of turnovers turned momentum back and forth through the second half.
Missouri was driving for a potential tying score when Maclin lined up at quarterback instead of Daniel and rolled to his right before throwing an interception to Reggie Smith. Oklahoma responded with a 56-yard drive and extended its lead to 23-10 on Brown's first TD run from 4 yards. Garrett Hartley bounced the extra-point try off the left upright.
That left the door open for Missouri to take the lead when Iglesias fumbled for the second time while returning a kickoff following Maclin's second touchdown run.
Jackson converted that takeaway into a score and Jeff Wolfert's extra point gave the Tigers a brief lead.