Spring is often cited as a time of renewal, and in recent years that has held true in Pac-10 football.

USC would renew its lease atop the conference annually, no matter who had bolted for NFL riches.

But this spring a different bird is chirping. It's a Duck, er, quacking.

After seven seasons of USC dominance, Oregon is the defending Pac-10 champion, and just about everyone has the Ducks pegged as the favorite to repeat.

Obviously, that means the Ducks have to prepare for the pressure of being a front-runner, right?

"We've never paid attention to any of that stuff -- the preseason rankings and everything like that means nothing to us," coach Chip Kelly said. "Our players can notice it. But our kids are smart kids. Because someone says you're supposed to be good doesn't mean a thing. All that stuff means nothing. We don't address it. We don't talk about it. We never talked about BCS rankings or Pac-10 championships until we won it. That's not a concern for us. It's about having a good spring practice and a good day in the weight room today."

So USC's "Win forever" under former coach Pete Carroll has become Kelly's "Win the day."

Of course, counting out the Trojans -- or really any team in the deep Pac-10 -- might be a mistake. Even Washington State, with 19 starters back, should be improved and more competitive.

Last spring, the Pac-10 welcomed back good talent at running back and on defense. Quarterback was a huge question mark. This year, eight starting quarterbacks return as well as an impressive cast of running backs, but a number of defenses take personnel hits.

So, just maybe, the days of high-flying, high-scoring games will return in the fall.

Kelly's Ducks certainly should be stout on offense. Ten starters, topped by quarterback Jeremiah Masoli and running back LaMichael James, are back from a unit that averaged 412 yards and a conference-high 36 points per game in 2009.

Of course, off-field events could change things a bit, so stay tuned.

Masoli leads a group of outstanding returning quarterbacks, a list that includes Washington's Jake Locker, Arizona's Nick Foles and Stanford's Andrew Luck.

Other returning starters at the position have something to prove: California's Kevin Riley, USC's Matt Barkley, UCLA's Kevin Prince and Washington State's Jeff Tuel.

Oregon State lost quarterback Sean Canfield, who won first-team All-Pac-10 honors in 2009, but 19 other starters are back. The chief question in the spring for the Beavers, who should again be in the thick of the Pac-10 race, is whether sophomore Ryan Katz quickly asserts himself as the starting quarterback or whether he gets challenged, particularly by Virginia transfer Peter Lalich.

Arizona State also is unsettled at quarterback, and the Sun Devils might feature the most wide-open competition between Michigan transfer Steven Threet and Brock Osweiler. Samson Szakacsy was supposed to be in the mix, but the elbow injury that has riddled him during his career has been acting up again, coach Dennis Erickson said Thursday.

Of course, Riley is hardly secure. He might face a challenge from sophomore Beau Sweeney.

Still, while the offensive firepower looks impressive, know that defense will be a huge issue this spring. Six teams lost at least five starters from that side of the ball: Arizona, Arizona State, California, Stanford, UCLA and USC.

As they say -- and Carroll's crews at USC proved -- defense wins championships.

But for the first time in a long time, the favored team heading into spring practices isn't the Trojans.