AUSTIN, Texas (AP) -- The Kansas State Wildcats charged toward their purple-clad fans behind the end zone to celebrate, then turned around and left the field flashing downward "Hook'em Horns!" signs.

"Texas who?" shouted Wildcats wide receiver Deon Murphy.

No longer undefeated Texas, that's who.

Kansas State scored three touchdowns on special teams and an interception Saturday and the Wildcats stunned the No. 7 Longhorns 41-21, handing Texas coach Mack Brown his worst home defeat in 10 years.

"We're not the biggest and strongest team in the country," Kansas State coach Ron Prince said. "We had to create some havoc."

The Wildcats (3-1, 1-0 Big 12) defense pounded Colt McCoy into his worst game with a relentless pass rush and four interceptions, thwarting the Longhorns and their quarterback for the second consecutive year. Kansas State beat Texas 45-42 last season and knocked Colt McCoy out of the game with a neck injury on the first drive.

Linebacker Ian Campbell returned the first pick 41 yards for a touchdown.

A jarring hit just before halftime left Colt McCoy woozy and sent him to the locker room early. He returned to start the third quarter but was taken out by team doctors in the final minutes of the game after showing symptoms of a mild concussion. Colt McCoy was 19 of 39 for 200 yards and a touchdown.

Jordy Nelson scored two touchdowns, including an 89-yard punt return in the third quarter, and James Johnson returned a kickoff 85 yards for another score.

Nelson's return made it 34-21 and practically ended Texas' hopes for a comeback. He also had 12 catches for 116 yards.

"Jordy's the people's champ," Murphy said. "It's in his blood."

By the time the Wildcats were done, they had scored the most points on Texas (4-1, 0-1) in Austin since 1997 when UCLA handed the Longhorns the infamous "Rout 66" loss, 66-3.

That blowout came under former coach John Mackovic. Until Saturday, Brown's worst home loss was a 35-17 defeat by Kansas State in 1999. It was also Texas' first loss in a Big 12 opener since it dropped the '98 opener to the Wildcats.

This one could be a devastating blow for the Longhorns as they head into next week's border showdown against Oklahoma, which was upset Saturday by Colorado.

"I think they were looking past us because they have Oklahoma coming up," Johnson said.

Even if they weren't, the two teams who were supposed to slug it out in the Big 12 South are both without a win after the first weekend of league play.

"We're not used to losing like that around here, especially like that," Brown said. "We've got to regroup."

K-State defenders said they stressed trying to get their hands up to tip Colt McCoy's passes. On Campbell's interception, the linebacker stunted on the pass rush, then stuck up his left hand to snag the throw at the line of scrimmage. Almost stunned to get the ball, Campbell coasted into the end zone with a load of Wildcats escorting him.

"We come full speed," Wildcats safety Courtney Herndon said. "We've been putting pressure on hitting the quarterback all year. That's what we like to do."

Colt McCoy's 26-yard TD pass to Quan Cosby tied it 14-14 before K-State struck with special teams for the first time on Johnson's 85-yard kickoff return.

Colt McCoy was shaken up when he threw another interception and was slammed to the turf by Clayton Cox. His legs were wobbly when he got up and was escorted to the locker room by trainers.

Brown said Colt McCoy stayed with the doctors during halftime and was cleared to play in the second half. Colt McCoy looked sharp when he led Texas to a touchdown that cut the Kansas State lead to 24-21.

"He was fired up, telling us we need to make these plays count," Texas offensive lineman Tony Hills said.

But another interception set up a K-State field goal. Colt McCoy now has nine interceptions after throwing 11 last season. Offensive coordinator Greg Davis said Colt McCoy was throwing up when doctors decided to take him out of the game with Texas trailing by 20.

Nelson's punt return stunned Texas just when it thought it could mount a comeback.

He fielded the punt at the 11, then moved to his right before cutting up field and weaved through tacklers. Only one Longhorn got a hand on him before he was in the clear and he still had 15 yards to the end zone when he started pumping his fist to celebrate.

"We don't fair catch very many," Nelson said.

By the end of the third quarter, the stadium was quiet except for K-State fans were chanting "Let's go Wildcats!" It wasn't long before Texas fans started raining boos as Colt McCoy and the Texas offense kept misfiring.

"He's our quarterback," Texas receiver Jones said. "He is one of the best and he is one of the leaders around here."

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