NORMAN, Okla. -- It came down to one play, and Steven Parker made it.

Parker batted away Bram Kohlhausen's 2-point conversion attempt with less than a minute left and the seventh-ranked Sooners survived a late comeback attempt to beat TCU 30-29 on Saturday night.

After trailing 30-13 in the fourth quarter, TCU had a chance to tie the game after Kohlhausen's 14-yard touchdown pass to Emanuel Porter with 51 seconds remaining. Instead, the Horned Frogs went for the win by attempting the 2-point conversion but were turned away by Parker.

"I just had a hard decision between staying on my receiver and coming to get the quarterback," Parker said. "And I kind of just played in between, and just timed my jump right. It's probably my most memorable moment in my football career."

TCU coach Gary Patterson defended his decision to go for the win.

"Our rule has always been to go get the win on the road," Patterson said. "To be honest, if (Parker) doesn't knock it down, there's a guy open in the back of the end zone to catch it. ... We came here to win."

Samaje Perine ran for 188 yards and a touchdown and Heisman Trophy contender Baker Mayfield completed 9 of 20 passes for 127 yards and two touchdowns for Oklahoma (10-1, 7-1 Big 12, No. 7 CFP, AP) before leaving with a head injury after the first half.

Oklahoma, winner of six straight, will have the opportunity to claim the Big 12 Championship next week when it plays Oklahoma State (No. 6 CFP, No. 4 AP).

Sooners coach Bob Stoops believes if they win that one, they should make it into the College Football Playoff.

"Sure, I would think so," Stoops said. "When you cannot be at your best and win, it's always a positive against a ranked team."

Without injured offensive stars Trevone Boykin and Josh Doctson, TCU (9-2, 6-2, No. 18 CFP, No. 11 AP) turned the ball over four times, leading to 24 Oklahoma points.

Freshman Foster Sawyer started in Boykin's place and had a strong first quarter, completing 7 of his first 8 passes for 103 yards and a touchdown that put the Horned Frogs up 7-0. He was just 1-of-10 after that with three interceptions and was eventually replaced midway through the third quarter by Kohlhausen.

Kohlhausen led the fourth quarter comeback attempt, completing 5 of 11 passes for 122 yards and two touchdowns. Aaron Green rushed for 127 yards -- 96 in the second half -- and a touchdown.

"That's what we do, we fight back, no matter who's on the field," Green said. "Second-string line, third- and second-string quarterback, freshmen at wideout, we just gave it our all. That's what we've been taught to do. Unfortunately, we just came up short."

With OU leading 23-7, Mayfield did not come out to start the second half. He was shaken up early in the second quarter by a helmet-to-helmet hit from TCU linebacker Ty Summers, who was ejected for targeting, but did finish the first half.

"Our trainers and doctors were constantly, with each series, every time Baker was off, checking him, asking him questions, making sure he was OK, and everything was checking out fine," Stoops said. "And then at halftime, they approached him again to go over some things and Baker admitted to having a headache, and that's when our doctors said we're not going to have him play.

"That threw us off in the second half. We weren't very consistent at all."

Trevor Knight played the rest of the game, completing 5 of 16 passes for 76 yards, with one interception.

Three plays into the third quarter, Perine got hurt after catching Knight's short pass and turning it into a 16-yard play. Unable to put any weight on his left foot, he came out for several minutes, but returned during Oklahoma's next possession.

Perine proved he was OK on a 72-yard touchdown run, putting OU up 30-13 with 7:55 left in the third.

"He had a slight ankle sprain," Stoops said. "It hurt him initially and once he gets on the sideline and they tape it again, he gets to moving on it again, then he trusts that it's OK. It's good and hopefully he'll heal up well."