By JOHN MARSHALL
AP College Football Writer

(AP) - The Pac-12 underwent some major changes during the offseason, adding four new coaches and an influx of fast-paced offenses.

The top of the conference still has a familiar look: Southern California in the South, Oregon in the North.

The Ducks never left, really. The Trojans had to fight their way back after some dark days.

Leveled by sanctions that led to the Reggie Bush Heisman Trophy giveback, USC was banned from the postseason the past two seasons and hamstrung by the loss of 30 scholarships over three years.

Postseason eligible again, USC is back, buoyed by the return of quarterback Matt Barkley, a Heisman Trophy favorite, the addition of Penn State leading rusher Silas Redd and 17 returning starters.

The Trojans aren't just the favorites to win the Pac-12 South. They're a front-runner to win the final BCS championship next January.

"We're two years removed from what was handed down as people saying `SC is over,' and being a preseason No. 1 team two years later is extremely exciting for our university and for our fans," USC coach Lane Kiffin said.

Oregon had been the Pac-12's dominant team while the Trojans were pushed away from the spotlight.

The Ducks played for a national championship two years ago and were a contender last season before winning the Rose Bowl for the first time in 95 years.

Oregon must replace running back LaMichael James and quarterback Darron Thomas, but these fast-flying Ducks have plenty of talented replacements ready and are poised for another season in the top 10.

And it's not just Trojans and Ducks.

They're the ones to beat, for sure, but Stanford and Utah have solid teams, there are new coaches at Arizona, Arizona State and UCLA, not to mention the always-entertaining Mike Leach taking over at Washington State.

It should be an interesting season.

___

NORTH

OREGON _ Key players: RB Kenjon Barner, RB De'Anthony Thomas, LB Michael Clay, DE Dion Jordan, WR Josh Huff, FS John Boyett. Returning starters: offense 5, defense 7.

Notes: Coach Chip Kelly met with the NFL's Tampa Bay Buccaneers about their head-coaching opening, but decided to stay in Eugene. ... The Ducks will have a tight battle to replace Thomas at QB. Sophomore Bryan Bennett threw for 376 yards and six touchdowns while Thomas was hurt last season, but freshman Marcus Mariota looked good in spring and could be a star in the making. ... James was a Heisman Trophy finalist and an All-American, but Barner and Thomas should make sure Oregon doesn't miss a fast-stepping beat.

___

STANFORD _ Key players: RB Stepfan Taylor, TE Zach Ertz, LB Chase Thomas, DE Ben Gardner, LB Shane Skov, WR Ty Montgomery. Returning starters: offense 6, defense 7.

Notes: Stanford's biggest hurdle will be replacing quarterback Andrew Luck, a two-time Heisman Trophy finalist who was the No. 1 overall pick in the NFL draft by the Indianapolis Colts. Brett Nottingham has a strong arm and was Luck's backup, but Josh Nunes has impressed the coaches with his game management. ... Skov was Stanford's leading tackler as a sophomore, but tore a ligament in his left knee the third game of the 2011 season. He will be suspended for the opener against San Jose State after being arrested for DUI last winter. ... Taylor ran for over 1,300 yards last season.

___

WASHINGTON _ Key players: QB Keith Price, CB Desmond Trufant, WR Kasen Williams, TE Austin Seferian-Jenkins, DE Josh Shirley. Returning starters: offense 6, defense 7.

Notes: Coming off the school's worst statistical defensive season, coach Steve Sarkisian replaced three defensive coaches, including coordinator Nick Holt. New coordinator Justin Wilcox has shifted the Huskies to more of a 3-4 defense, which appeared to free up the defenders in Washington's spring game. ... The Huskies have to replace top running back Chris Polk and have plenty of question marks on the offensive line. ... Price was stellar in his first season as a starter, setting a team record by completing 66.9 percent of his passes while throwing for over 3,000 yards and 33 TDs.

___

CALIFORNIA _ Key players: QB Zach Maynard, RB Isi Sofele, RB C.J. Anderson, WR Keenan Allen, DE Mustafa Jalil, NG Aaron Tipoti. Returning starters: offense 6, defense 6.

Notes: Sofele and Anderson give the Bears a nice 1-2 punch, but there are a couple of holes to fill on the offensive line. ... Maynard completed 57 percent of his passes for nearly 3,000 yards, but had 12 interceptions to go with 17 TDs. ... Allen, one of the most dynamic receivers in the conference, had ankle surgery in the spring, but is expected to be ready for the season opener. ... Cal opens remodeled Memorial Stadium against Nevada on Sept. 1.