PASADENA, Calif. - Top-ranked Southern California laid out its case for the national championship by dominating No. 4 Michigan with a 28-14 victory Thursday in the Rose Bowl.

Matt Leinart threw three touchdown passes and caught another to lead the Trojans past the Wolverines with a performance that should be enough to persuade voters to leave USC atop the poll.

The Associated Press' No. 1 team has never dropped in the rankings after winning its bowl, and it doesn't look as though it will happen this time, either.

While the Trojans are primed to win their first title in 25 years, they would have to share it. Voters for the USA Today/ESPN coaches' poll are obligated to crown the winner of Sunday's Sugar Bowl between No. 2 LSU and No. 3 Oklahoma, playing in the BCS championship game.

Leinart, the game's MVP, shredded the nation's sixth-ranked pass defense for 327 yards, and the Trojans (12-1) had a season-high nine sacks and even blocked a field goal by Michigan (10-3).

The game's signature play came late in the third quarter when Mike Williams took a reverse handoff from Hershel Dennis and flicked an easy pass to Leinart, who jogged in for a 15-yard score that made it 28-7.

With the big lead, all the Trojans needed to do was run out the clock - and start waiting for the final AP poll early Monday morning. The fans had their answer already, chanting ''We're No. 1! We're No. 1!'' during the final minutes.

The victory caps USC's return to prominence after years of mediocrity. The Trojans went 31-29 in the five years before Pete Carroll brought his youthful enthusiasm to one of college football's traditional powers.

Fired twice in the NFL for being too soft, Carroll's style was a perfect fit in Los Angeles. After losing five of his first seven games, Carroll has a 27-4 mark.

He has combined his aggressive defensive style with offensive coordinator Norm Chow's sophisticated passing game to create a national power.

The Wolverines allowed only five touchdown passes all year before running into USC. Keary Colbert had six catches for 149 yards and two touchdowns, and LenDale White had the other scoring reception. The Trojans needed less than five minutes on its four scoring drives.