But the winner of today's game likely will be No. 1.
In the 2007 preseason polls.
"It's probably the biggest bowl game for next year and everyone knows that," Michigan running back Mike Hart said.
Count USC quarterback John David Booty among the believers.
"I think even the loser will be No. 2 or 3," he said.
If recent form holds, USC or Michigan, both loaded with key junior starters and talented underclassmen, will follow the path of Ohio State. The Buckeyes parlayed a Fiesta Bowl win over Notre Dame last January into a No. 1 preseason ranking and held it from start to finish in the regular season.
Ohio State plays Florida on Jan. 8 in the BCS title game.
Some college football observers, looking ahead to the 2008 bowl season, regard this year's USC-Michigan matchup as a possible preview to the next BCS title game in New Orleans.
"I could definitely see that happening," Michigan safety Jamar Adams said.
Both teams feature junior quarterbacks who will probably receive Heisman Trophy consideration, especially if they play well today. Booty and Michigan's Chad Henne could be next season's Troy Smith and Brady Quinn, who played in the 2005 Fiesta Bowl and finished first and third in recent Heisman balloting.
Hart, who averaged 126 yards rushing a game this season, returns after finishing fifth in Heisman balloting. All-American tackle Jake Long also will be back. USC returns all of its running backs and All-American tackle Sam Baker.
The Trojans lose only one starter on defense and expect to welcome back safety Josh Pinkard, who suffered a season-ending knee injury in the opener. The Wolverines return half as many defensive starters, but among them is linebacker Shawn Crable, who announced recently that he would return for his final season of eligibility.
"It could happen," USC defensive end Lawrence Jackson said of a rematch. "But there is a long way to go and a lot of games to be played before we get to that point."
USC and Michigan need look no further than their final regular-season games to validate Jackson's statement.
Both squandered opportunities to play in this year's BCS title game by losing to their most bitter rivals.
On Nov. 18 at Columbus, Ohio, unbeaten Michigan fell, 42-39, to the top-ranked and undefeated Buckeyes.
On Dec. 2, USC was second in the BCS standings and needed only a victory over UCLA to advance to the BCS title game for the third consecutive year. But UCLA's defense harassed Booty and shut down the Trojans' running game in a 13-9 upset at the Rose Bowl.
The losses put both the Trojans and the Wolverines in the Rose Bowl game for the third time in four years.
Players and coaches from both teams acknowledged disappointment at missing the chance to play Ohio State in Glendale, Ariz., but that appeared to have dissipated as today's game drew near.
"I haven't really had to sell it," Michigan Coach Lloyd Carr said.
USC Coach Pete Carroll said the Trojans had moved past the UCLA loss and were prepared for their Rose Bowl opportunity.
"We're looking forward to a big explosion on game day for our team, and I know their team will be loaded and ready to go too," he said.
In regard to next season, it's worth noting that the Rose Bowl helped launch other championship drives in the last few years.
For example, USC finished its 2003 season with a 28-14 win over Michigan on Jan. 1, 2004. The victory clinched the Associated Press national title and installed USC as the No. 1 team in the 2004 preseason polls. The Trojans finished unbeaten and defeated Oklahoma in the 2005 BCS title game.
Texas defeated Michigan in the 2005 Rose Bowl and began the next season ranked second behind USC. The Longhorns returned to Pasadena last Jan. 4 and won the BCS title with a 41-38 victory that ended the Trojans' 34-game winning streak.
For Michigan, just winning a bowl game would be sufficient reward.
The Wolverines have not won in the postseason since 2003, when they defeated Florida in the Outback Bowl. Michigan has since lost to the Trojans and Texas in the Rose Bowl and to Nebraska in the Alamo Bowl.
"I haven't won a bowl game since I've been here," Long said. "A lot of the guys haven't won one. We don't know what it's like to experience that. We want to prove that we can finish a season."
For the first time in four years, USC must prove that it can play well without a championship on the line.
And the Trojans will try to do it against a Michigan team that believes it should be playing for the title. The Wolverines were No. 3 in the BCS before USC's loss to UCLA, but the next week were leapfrogged by Florida, which jumped from No. 4 to No. 2 in the final standings.
Michigan's offense features Henne, Hart and receivers Mario Manningham, Steve Breaston and Adrian Arrington. The Wolverines rush for 189 yards a game and pass for 186.
"They're the best offense we've faced all year," Carroll said.
The 5-foot-9 Hart has rushed for 1,515 yards and 14 touchdowns.
"He looks practically untackle-able sometimes when he's in the hole," USC linebacker Oscar Lua said. "They swarm on him, but he just bounces off like a pinball."
Long leads an offensive line that clears the way for Hart and has done a fair job protecting Henne, who has passed for 20 touchdowns with seven interceptions and has been sacked 18 times.
Asked if he thought the Trojans would have trouble getting to Michigan's quarterback, Jackson said: "I don't think so. They're not the big bad wolf and we're not the three little pigs."
Meanwhile, a USC offense coming off its worst performance of the season will try to hold off a Michigan front seven led by All-American end LaMarr Woodley and tackle Alan Branch.
The Wolverines are ranked seventh nationally in total defense and first against the run, surrendering 43 yards a game.
Woodley, the Lombardi Award winner as college football's top lineman, has 11 of Michigan's 41 sacks and is eager to test his skills against a USC line looking for redemption after a poor performance against UCLA, whose defensive ends, Bruce Davis and Justin Hickman, harassed Booty throughout the game.
"It definitely gives you encouragement when you see guys play your position, doing some of the things that you do," Woodley said. "You kind of get an idea in the end that I can do the same thing they've done."
USC offensive coordinator Lane Kiffin said a consistent running attack would be crucial against the Wolverines. The Trojans were held to a season-low 55 yards rushing against UCLA, but they should be buoyed by tailback Chauncey Washington's return to full strength.
"In the UCLA game we had too many negative runs, too many runs for minus-one, minus-two. And this run game has been built over the years on not having that," Kiffin said. "We're looking for four-yard runs to keep us in manageable down and distance for our quarterback."
That would please Booty, who has passed for 25 touchdowns with nine interceptions.
"Hopefully, we can keep me off my butt a little bit because we've definitely got to seal guys to make big plays," he said.
Booty will be looking for senior flanker Steve Smith, who is playing in his final game, and junior split end Dwayne Jarrett, who also might be finishing his college career. Jarrett, a two-time All-American, will decide whether to declare for the NFL draft after the Rose Bowl.
The Michigan secondary features All-American cornerback Leon Hall, but the group is considered vulnerable.
"We have a lot of great receivers and then our running backs are definitely going to be healthy, so I think it's going to be a challenge to try and stop our offense," Jarrett said. "They have a great defense, but I think we have too many weapons."