Texas was a two touchdown underdog, but outplayed Oklahoma in every phase of the game to upset the Sooners 36-20 on Saturday at the Cotton Bowl in Dallas.
Each team kicked field goals on their opening possession, with Anthony Fera booting a 31-yarder to give the Longhorns their first lead over OU since 2009.
The Sooners answered with a 34-yard field goal from Michael Hunnicutt to tie the game at 3.
Then the two teams swapped turnovers, with OU recovering a fumble by Joe Bergeron.
The Sooners turned it right back over, though, as Chris Whaley intercepted a pass by Blake Bell, returning it 31 yards for the touchdown to put UT on top 10-3.
The score stayed that way until midway through the second quarter, when Case McCoy passed to Marcus Johnson for a 59-yard touchdown to give Texas a 17-3 advantage.
The TD capped a six-play, 73-yard drive.
The Longhorns got a 50-yard field goal from Fera to make it 20-3 with 3:22 to play in the first half.
Oklahoma then got a big play they needed, as Roy Finch returned the enusing kickoff 73 yards to the Texas 27.
It took OU five plays to score, with Damien Williams running it in from three yards out to make it 20-10 with just 1:06 to play in the second quarter.
Texas appeared to be content to run the time out in the half, but McCoy passed to Jaxon Shipley for an 18-yard gain that got UT into field goal range.
As time expired in the first half, Fera kicked a 43-yard field goal to take a 23-10 lead to the lockerroom.
Oklahoma got the ball to start the second half and drove to a field goal, with Hunnicutt hitting a 37-yarder to make it 23-13.
It stayed that way until the UT special teams made a big play, with Daje Johnson returning a punt 85 yards for a touchdown.
It was the first time OU had allowed a punt return for a touchdown since Jeremy Bloom of Colorado did it against the Sooners in the 2002 Big 12 Championship Game.
The extra point was blocked, and the Longhorns lead was 29-13 midway through the third quarter.
Another Blake Bell interception set up the next UT score.
Duke Thomas picked off a Bell pass at the Longhorn 30-yard line.
Bell was just 12 of 26 passing for 133 yards with two interceptions.
From there, Texas marched 70 yards in nine plays, with McCoy passing to Mike Davis for a 38-yard touchdown to put the Horns in control by 23, 36-13.
McCoy was efficient for the Longhorns, completing 13 of 21 passes for 190 yards and two touchdowns.
OU showed signs of life early in the fourth quarter, when Geneo Grissom intercepted McCoy, and the big defensive lineman rumbled 55 yards for a touchdown, making it
36-20 Texas, and getting the Sooners to within two scores.
Oklahoma had a chance to cut into the lead even more, but on 4th and 13 from the Texas 14, Jackson Jeffcoat sacked Blake Bell.
The Longhorns then ran out the clock on their possession to end the game, and score their biggest win over OU since 2005.
OU was just two for 13 on third down conversions, while Texas was 13 of 20, converting key plays time after time.
OU suffers their first loss of the year to drop to 5-1, 2-1 in the Big 12.
Texas improves to 4-2, and 3-0 in conference play.