NORMAN, Okla. -- In the final minute of regulation, Oklahoma's defense was reeling and TCU's offense was rolling.

So TCU coach Gary Patterson decided to go for two after the No. 18 Horned Frogs scored in the final minute.

But safety Steven Parker leaped into the air to deflect Bram Kohlhausen's pass and No. 7 Oklahoma escaped with a 30-29 win Saturday night at Gaylord Family-Oklahoma Memorial Stadium.

Samaje Perine ran for 188 yards and a touchdown for the Sooners (10-1, 7-1 Big 12).

But the Sooners lost quarterback Baker Mayfield to an apparent head injury and the junior didn't return after halftime.

Knight was the Sooners' starter for much of the last two seasons before Mayfield beat him out in preseason camp.

Mayfield, who had vaulted into the Heisman Trophy race with his performance in a win at Baylor a week earlier, appeared to suffer a head injury after taking a hit from TCU linebacker Ty Summers early in the second quarter. Summers was ejected for targeting on the play.

Mayfield remained in the game and threw a touchdown pass later in the half. He returned after halftime without a helmet and Trevor Knight took over.

Oklahoma's offense looked in trouble early in the second half when Perine and Joe Mixon, who shares carries with Perine, went out with apparent ankle injuries on successive drives.

But Perine returned quickly and, on his first carry, ran for a 72-yard touchdown. It was the longest run of Perine's career.

Mayfield threw for 127 yards and two touchdowns in the first half.

Knight was 5 for 16 for 76 yards and an interception.

TCU also changed quarterbacks during the game, with senior Kohlhausen replacing redshirt freshman Foster Sawyer early in the second half after Sawyer's third interception of the game early in the third quarter.

Kohlhausen gave the Horned Frogs a boost, throwing for 122 yards and two touchdowns.

Aaron Green ran for 126 yards and a touchdown for TCU.

The Sooners have won six consecutive games since losing to Texas on Oct. 10. TCU fell to 9-2 and 6-2.

Without starting quarterback Trevone Boykin and star wide receiver Josh Doctson, TCU's offense figured to be in trouble.

But redshirt freshman Foster Sawyer, making his first career start after coming on in relief after Boykin suffered an ankle sprain a week earlier against Kansas, got off to a hot start with the help of receiver Kolby Listenbee.

Sawyer hit Listenbee for two long passes on the Horned Frogs' second drive, the second a 37-yard touchdown pass.

The defense also did its part early, forcing the Sooners to punt on their first three possessions.

But, late in the first quarter, Oklahoma cornerback Zack Sanchez intercepted Sawyer's pass and the Sooners quickly drove 43 yards for their first touchdown -- a 21-yard pass to Sterling Shepard from Mayfield.

Sanchez's interception was his first of two in the half.

After the Horned Frogs' initial 97-yard drive, TCU managed only 60 yards the rest of the half, just 17 passing.

The Sooners had several chances to blow the game open but had to settle for Austin Seibert field goals on three drives and led 23-7 at the break.

NOTES: TCU LB Ty Summers was ejected for targeting early in the second quarter after a sack of Oklahoma QB Baker Mayfield. Montrel Wilson replaced Summers. ... Oklahoma RB Samaje Perine surpassed 1,000 yards rushing for the season early in the first quarter. ... In addition to missing QB Trevone Boykin and WR Josh Doctson, the Horned Frogs were without C Joey Hunt, who was injured in practice during the week. Austin Schlottman started in his spot. ... On Senior Day, Oklahoma LB Frank Shannon started in place of Jordan Evans, though Evans wound up playing the majority of the game. ... LB P.L. Lindley was named the Don Key Award, given to the Oklahoma senior or seniors who display all-around excellence. ... Hadley Wyatt, a 6-year-old Oklahoma State fan who was injured in the homecoming crash on Oct. 24 and treated at OU Medical Center, served as an honorary captain for the Sooners before the game. ... Oklahoma finishes the regular season at Oklahoma State on Saturday. TCU hosts Baylor on Friday.