STILLWATER, Okla. (AP) -- Just like that, everything has changed for TCU.

Mason Rudolph passed for 352 yards and five touchdowns, James Washington caught five passes for 184 yards and three touchdowns, and the 12th-ranked Cowboys pulled a 49-29 upset of the fifth-ranked and previously unbeaten Horned Frogs.

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Now, TCU probably is out of the national title race and there's a big dent in Trevone Boykin's Heisman hopes. Making matters worse, Josh Doctson, the nation's leader in yards receiving, left the game with a left wrist injury and didn't return.

TCU coach Gary Patterson said the Horned Frogs won't quit.

"The sky's not going to be falling," he said. "You're going to write the sky is falling, and I'm going to try to beat Kansas next week."

Boykin, who has generated Heisman buzz all season, passed for 445 yards and ran for 73 yards and two touchdowns, but he also threw a career-high four interceptions.

"I just feel we did some things on our side of the ball that we normally don't do, and they capitalized off of every turnover we had," Boykin said. "You're not going to come into an environment like this and have four turnovers and expect to win a game."

TCU (8-1, 5-1 Big 12, No. 8 CFP) gained 663 yards, but the Horned Frogs were held scoreless in the red zone twice as their 16-game win streak was snapped.

Doctson's injury was a game changer.

"You go in with a game plan, and the game plan is to throw to number nine, and then number nine's not there anymore," Patterson said. "Your whole set of rules change for this offense, because they set plays up for people."

Shaun Nixon had career highs of nine catches and 146 yards, and KaVontae Turpin added seven catches for 107 yards for the Horned Frogs.

Washington had touchdown catches of 48 and 50 yards in the first nine minutes, then Rudolph connected with Jeff Carr on a screen pass for a 12-yard score that put the Cowboys (9-0, 6-0, No. 14 CFP) up 21-9 early in the second quarter.

After stopping TCU on fourth down in the red zone, Oklahoma State struck quickly. Rudolph connected with Marcell Ateman for an 83-yard touchdown pass to put the Cowboys up 28-9.

Early in the second half, Whitener intercepted Boykin and returned it to the TCU 1-yard line. J.W. Walsh scored on the next play to make it 35-9.

Whitener took Boykin's fourth interception back 42 yards for a touchdown with 44 seconds remaining.

TCU still hopes to make some noise.

"Maybe the playoffs are out of line, but we can beat Oklahoma and Baylor, and you're 11-1, and somebody else can make that decision," Patterson said.

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