NORMAN, Okla. - His ankle injured and his team defeated, Oklahoma running back Adrian Peterson had few words to explain what had just happened.

“Right now, I’m kind of shocked,” he said.

He wasn’t the only one.

TCU came up with its biggest upset in 45 years, stifling Peterson and beating No. 7 Oklahoma 17-10 Saturday in the Sooners’ first home loss since 2001 and first loss in September under coach Bob Stoops.

The Horned Frogs (1-0) came out with a plan to stop Peterson and make Oklahoma quarterback Paul Thompson beat them in his first career start. It worked.

While Peterson, the Heisman Trophy runner-up as a freshman last year, was held to 63 yards on 22 carries, TCU’s Tye Gunn threw for 226 yards and a touchdown and Robert Merrill scored the decisive touchdown on a 2-yard run with 11:56.

The Horned Frogs took advantage of a fumble by Sooners backup quarterback Rhett Bomar. Bomar, who lost a quarterback competition to Thompson but did well enough to earn playing time, fumbled while retreating and trying to spin away from Jamison Newby. David Hawthorne picked up the ball at the TCU 17, and Merrill took an option pitch from Gunn and scored untouched four plays later. It was one of four turnovers — including four fumbles — by the Sooners.

“When we got the turnovers, their heads dropped,” Hawthorne said. “It wasn’t the same OU team that you saw last year.”

The Sooners had one final chance with 2:05 left, but Thompson — charged with replacing 2003 Heisman winner Jason White — fumbled on a fourth down play with 1:03 left and the Horned Frogs recovered and ran out the clock.

Oklahoma fans quickly filed out while TCU players gathered by the band for the fight song amid the cheers of two sections of purple-clad Frogs fans.

“We were just trying to make a statement that, ’Hey, we’re here,”’ TCU offensive tackle Herbert Taylor said. “The Frogs come to play. We play hard.”

The Horned Frogs last beat a team so highly ranked on Oct. 29, 1960, when they defeated No. 7 Baylor 14-6. TCU also upset No. 2 Texas 14-9 on Nov. 14, 1959.

“I think that nine times out of 10, Oklahoma wins this game,” TCU coach Gary Patterson said. “Today was our one. We got a chance to show off on national TV and show America that TCU is not gone.”

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Peterson left the game briefly late in the third quarter with a right ankle injury. He returned early in the fourth quarter after having the ankle heavily taped, but lost yardage on three of his five carries. He said he didn’t know exactly what was wrong with the ankle, and team doctors would have to re-examine it.

“It’s feeling pretty good,” he said. “It feels better than it did.”

But Peterson was ineffective long before the injury. He had only 5 yards on eight first-half carries and gained 7 yards on a pair of receptions.