PASADENA, California (Ticker) - Southern California held off a final challenge before punching its ticket to Miami.
Heisman Trophy hopeful Reggie Bush scored on two long touchdown runs and accounted for 335 all-purpose yards as the top-ranked Trojans clinched a berth in the national championship game with a 29-24 Pac-10 Conference victory over UCLA.
USC, which shared the national title last season with Louisiana State, will learn its Orange Bowl opponent on Sunday when the BCS pairings are announced. The Trojans went wire-to-wire as the nation's No. 1 team.
"It's a great challenge to begin the season No. 1 and an even bigger challenge to end it there," USC coach Pete Carroll said.
UCLA held Matt Leinart, who completed 24-of-34 passes for 242 yards, without a touchdown pass for the first time in his 25 starts at USC. Ryan Killeen kicked a school-record five field goals for the Trojans, who were an uncharacteristic 1-for-13 on third-down conversions and kept out of the end zone in the second half.
"I think they put a lot of pressure on me to make quick decisions, but I think we made enough big plays and we did enough obviously to win the game," Leinart said.
Bush burned the Bruins with his speed, reaching the end zone in the first half on runs of 65 and 81 yards to help USC (12-0) complete an undefeated regular season and extend its winning streak to 21 games.
"They definitely made it tough for us," Bush said. "They had three weeks to prepare for us, so we expected nothing short of a great game and for them to come out with a great effort."
Bush rushed for a career-high 204 yards on 15 carries, caught six passes for 73 yards and added 58 return yards.
"Reggie," he changed the game tonight," Leinart said.
"I have no advice in terms of stopping him," UCLA coach Karl Dorrell added. "No one has been able to stop him."
It took just two plays for Bush to score his first touchdown as he raced up the middle with a handoff. The Trojans threatened to turn the game into a rout as Killeen kicked a 37-yard field goal on USC's second possession to make it 10-0.
UCLA's defense stiffened and the Bruins climbed within 10-7 on Craig Bragg's 96-yard punt return with 9:51 left in the first half.
Down 20-10 at the break, UCLA put a scare into the Trojans in the second half, closing to 23-17 on Manny White's nine-yard TD run with 1:35 left in the third quarter.
After Killeen kicked field goals of 36 and 34 yards in the fourth quarter, the Bruins again closed within a score on Drew Olson's four-yard touchdown pass to Mercedes Lewis with 2:20 left. It was only the second TD allowed by USC in the fourth quarter this season.
"We outplayed USC in the second half," Dorrell said. "Our offense kind of sputtered in the first half."
Bush gave the Bruins a glimmer of hope by fumbling inside the UCLA 15 with 53 seconds remaining, but safety Jason Leach sealed the win with an interception on the next play.
"We had a target on our chests all year," Leinart said. "We were ranked No. 1 throughout the whole season and we just kept battling."
Olson completed 20-of-34 passes for 278 yards, but the Trojans took away the Bruins' running game. UCLA rushed for just 17 yards on 25 carries.
The Trojans posted their sixth straight win over the Bruins, increasing their lead in the series to 40-27-7.