EUGENE — There have been times this season when the USC Trojans have been labeled sluggish and unimpressive.

EUGENE — There have been times this season when the USC Trojans have been labeled sluggish and unimpressive.

Don't expect that today when the No. 9 Trojans (6-1, 3-1 Pacific-10) visit No. 5 Oregon (also 6-1, 3-1) at Autzen Stadium. Conference standing is not the only issue. There could be national championship implications given the unpredictability of the season so far.

"This is the kind of stuff that really excites you about conference play. You have a team that's really hot, and you have to beat them if you're going to have a chance to win your league. They have all of the elements that draw your focus. They have got great players, and we're playing at a very tough place and all that," Trojans coach Pete Carroll said.

During a stretch of Pac-10 play, Southern California was less than dazzling in a 27-24 victory over Washington, then was upset 24-23 by Stanford before a 20-13 victory over an Arizona team that has won only two games so far.

At stake today is Pac-10 title hopes. UCLA and Arizona State are still unbeaten in conference and will play each other on Nov. 10. Oregon and USC each have one loss in the league. Cal defeated the Ducks 31-24 at Autzen on Sept. 29.

"We both have a lot at stake," USC tailback Stafon Johnson said. "Both of us can't afford to lose."

The game has widely been billed as a showdown between one of the nation's best offenses in Oregon and USC's powerful defense. The Trojans are allowing only 252 yards a game, while the Ducks average 551 yards in a speedy spread-option offense.

But Ducks coach Mike Bellotti suggested it may come down to something unexpected at Autzen.

"The reality is, probably, our defense and their offense and both teams' special teams are going to have the biggest say," Bellotti said. "Because typically in great football games I think special teams is the unsung hero, so to speak. And the bottom line is turnovers and takeaways."

USC settled a lingering question about its offense on Thursday when Carroll declared that Mark Sanchez would make his third start at quarterback.

John David Booty had thrown in practice but continued to nurse a broken middle finger on this throwing hand.

Booty did not have a setback in practice and would suit up for Saturday's game, Carroll said.

Sanchez passed for 130 yards and a touchdown but was intercepted twice against Arizona. The third-year sophomore improved in last weekend's 38-0 victory over Notre Dame, throwing for 235 yards and four TDs with no interceptions.

USC has won the last three games against the Ducks, including last year's 35-10 victory in Los Angeles. The Trojans have won their last two in Eugene.

It is the first time in Autzen Stadium's 41-year history that two top 10 teams will meet.