No. 20 Oklahoma State rallied from an 18-point deficit to clinch a spot in the Big 12 championship game with a thrilling 40-34 double-overtime win over BYU on Saturday in rainy Stillwater, Okla.

Ollie Gordon II rushed for 166 yards and five touchdowns, including scores in the final minute of regulation and in each OT session, to help secure the Cowboys (9-3, 7-2 Big 12) a championship showdown with No. 7 Texas next Saturday in Arlington, Texas.

Cowboys safety Trey Rucker stripped the ball out of Cougars tight end Isaac Rex's hands and recovered the fumble to clinch the win after Gordon put the Cowboys up by six on their possession in the second overtime.

BYU (5-7, 2-7) led much of the way -- including a 24-6 halftime lead -- and then forced overtime with a gritty, last-minute drive for a game-tying field goal as time expired. The Cougars' first season in the Big 12 ended on a turnover and with five consecutive losses in conference action.

Oklahoma State's Alan Bowman threw for 321 yards on 31-for-47 passing, including 132 yards and nine receptions to Leon Johnson III. Brennan Presley added 90 yards receiving for OSU, which piled up 503 yards of offense.

Jake Retzlaff completed 14 of 30 passes for 161 yards for BYU, while Aidan Robbins rushed for 74 yards as BYU had 327 yards of offense.

Gordon put OSU up 27-24 on a 15-yard touchdown with under a minute to go after the Cowboys had trailed since the first quarter. BYU kept it to a three-point game by blocking the extra-point attempt.

BYU forced overtime thanks to a 48-yard field goal by Will Ferrin as time expired in regulation.

Gordon scored two other times in the second half from 2 yards out as OSU erased BYU's big lead.

Oklahoma State took a 6-0 lead on two Alex Hale field goals.

The Cougars went ahead 7-6 after Retzlaff scored on a 2-yard TD run. Eddie Heckard put BYU up 14-6 with a 13-yard interception return.

BYU went into the locker room with a 24-6 lead thanks to an 11-yard touchdown run by Keelon Marion and a 42-yard Ferrin field goal.

In overtime, BYU went up by a touchdown on a 6-yard Retzlaff keeper.

Oklahoma State answered with Gordon's fourth touchdown from 3 yards out. Gordon broke free from a tackle to score the go-ahead TD from 2 yards out in the second overtime.

--Field Level Media