While UCLA linebacker Akeem Ayers sprinted up the field with a 77-yard interception return, Houston's Case Keenum disturbingly remained motionless behind him, facemask digging into the Rose Bowl turf.

On the same night the Bruins straightened out their season, the No. 23 Cougars might have headed into a spiral after their star quarterback's latest injury.

Johnathan Franklin rushed for 158 yards and three touchdowns, and UCLA rolled to a 31-13 victory Saturday night over Houston, which lost Keenum for the second straight week when the fifth-leading passer in NCAA history made an ill-advised attempt at a tackle.

"It doesn't boggle your mind. It's football," Houston coach Kevin Sumlin said. "It's unfortunate for us tonight, but UCLA played well and answered the physical challenge. They're a talented team. They were trying to find themselves, and I was hoping it wouldn't happen tonight, but it did."

Kevin Prince passed for 99 yards and rushed for a score as the Bruins (1-2) ricocheted back from a humiliating 35-0 loss to Stanford last week with a stunningly one-sided win. The Cougars (2-1) had the nation's highest-scoring offense last season and again through two games this year after scoring 122 points, but they didn't score a touchdown at the Rose Bowl until James Cleveland's diving 10-yard catch with 11:39 to play.

"We watched so much film throughout the week that we pretty much knew everything Houston was trying to do," said safety Rahim Moore, who returned a second-quarter interception 42 yards from deep in Bruins territory. "With that type of offense being so dynamic, we didn't let it confuse us. You know what's funny? Nobody gave us a chance. They said the defense couldn't make plays. They were giving us all kinds of letter grades that were bad, and we took it personal."

The powerful Cougars' chances for a Conference USA title could be slim without Keenum, who had been the model of durability in his first three seasons.

After Ayers picked off Keenum's throw near the goal line and then dodged the quarterback's tackle in the second quarter, Keenum remained down for two minutes before walking gingerly to the sideline. He eventually left on a golf cart, apparently favoring his right knee.

Sumlin only confirmed Keenum has a leg injury, saying he'll be re-evaluated back home. Houston then lost Cotton Turner, Keenum's backup, to a shoulder injury early in the second half.

"I'm sure (Keenum's injury) affected us some mentally, but when both of them go out, then you have a real effect on what we can do," Sumlin said.

Keenum passed for more than 5,000 yards and led the NCAA in total offense in each of the past two seasons, but the senior incurred a concussion last week while trying to make a tackle after an interception by UTEP's Travaun Nixon. The Cougars didn't confirm he would play against UCLA until he took the field with the offense.

Keenum was 10 of 18 for 83 yards, but also threw two interceptions.

UCLA already was up 21-3 on the Cougars at the time of Keenum's injury, rolling toward a victory that will stop much of the complaining about coach Rick Neuheisel's third season at his alma mater. With last week's embarrassment from Stanford and next week's trip to No. 6 Texas, the Bruins faced the distinct possibility of a winless September.

"When you start the season as we have, with some difficult losses and embarrassing features within those losses, there's only one way to dig your way out of it," Neuheisel said. "It was very exciting stuff, and hopefully it's a precursor of what's to come."

After rushing for 308 yards last week, Houston managed just 108 against UCLA's defensive front, which gave up 524 yards on the ground in its first two games.

The injuries led Sumlin to burn the redshirt of touted freshman quarterback Terrance Broadway, who led a 13-play, 74-yard scoring drive in the fourth quarter capped by a sharp throw to Cleveland. Broadway led another late scoring drive, finishing 5 of 8 for 84 yards.

"He was very poised, very impressive," Cleveland said of the freshman passer. "I don't even know how many of our quarterbacks went down, but he can step in."

Prince again wasn't exceptionally sharp, going 9 for 17 with another interception, but UCLA's Pistol offense was much more effective than in its first two games. The Bruins' ground game was productive early, while interceptions and kick returns set up UCLA for several short scoring drives.

"It's obviously a relief, coming off last week," Prince said. "It helps so much in terms of the whole team's confidence."