BOULDER, Colo. (AP) -- Jason White threw three touchdown passes, including a 59-yarder to Mark Clayton with 1:59 left, as top-ranked Oklahoma survived a scare to beat Colorado 34-20 Saturday night.
The Sooners (8-0, 4-0 Big 12) built a 27-7 third-quarter lead before Colorado closed to 27-20 with two touchdowns in the fourth.
Facing a third-and-6 from their 41 with 2:13 remaining, White hit Clayton along the left sideline, and the receiver cut back and outraced the Colorado secondary for the clinching score.
Joel Klatt threw three touchdown passes for Colorado (3-5, 1-3), which entered the game with the worst scoring defense in the country (40.1) but played the Sooners tough.
Colorado, smothered by Oklahoma's defense for most of the second and third quarters, pulled off a fake punt and a fake field goal on a 76-yard scoring drive early in the fourth.
Punter John Torp's 20-yard run on the fake punt was Colorado's initial first down rushing of the game. The Buffaloes also were successful on a fake field goal when their pass was intercepted but the Sooners were whistled for pass interference. Tailback Brian Calhoun capped the drive, turning a short pass into a 21-yard scoring play with 11:41 remaining.
The Buffaloes then went 61 yards in nine plays, with Klatt passing 9 yards to Derek McCoy for the score with 5:03 left. Mason Crosby's extra point was blocked by Brodney Pool, leaving the Sooners with a 27-20 lead.
White and Clayton hooked up five plays later.
Oklahoma scored on its first two possessions en route to a 17-7 halftime lead.
The Sooners needed only 59 seconds and 2:29 to score their first two touchdowns.
On the third play of their first possession, White hit a wide-open Brandon Jones on a 54-yard touchdown pass barely three minutes into the game.
After a Colorado punt, Renaldo Works broke off a 38-yard run, with a face-mask penalty tacked on, putting Oklahoma at the Colorado 17. After a pass-interference penalty against Colorado, Works ran 2 yards for a 14-0 lead with 6:03 left in the first quarter.
Colorado responded with a 56-yard, nine-play drive after Jeremy Bloom returned a kickoff 36 yards to the Buffs' 44.
Klatt was 5-for-6 on the drive, including an 18-yarder to D.J. Hackett, and capped it by finding Hackett on a 3-yard touchdown throw.
The Buffaloes appeared primed to tie it after an Oklahoma fumble, driving to the Sooners 8. But Daniel Jolly fumbled when hit by Brandon Everage, and Oklahoma's Donte Nicholson recovered.
Later in the quarter, Trey DiCarlo kicked a 42-yard field goal. Another Colorado penalty - for pass interference - helped set up the kick.
Oklahoma took the second-half kickoff and marched 77 yards for a 20-yard field goal by DiCarlo.
After an exchange of turnovers, White capped a 39-yard drive with a 15-yard scoring pass to Clayton, putting the Sooners up 27-7 with 1:37 left in the third quarter.