LOS ANGELES — Pete Carroll loves challenges and the NFL game. The Seattle Seahawks offered both, and not even Southern California could compete.

Carroll ended his nine-year tenure with the Trojans yesterday, leaving behind a program facing multiple woes for a lucrative deal to coach the Seahawks.

"If you know anything about me, you know I can't pass up this challenge," Carroll said.

USC quarterback Matt Barkley also said quarterbacks coach Jeremy Bates is leaving with Carroll after just one season, presumably to become the Seahawks' offensive coordinator.

Carroll was 97-19, won seven Pac-10 titles and two national championships at USC, but the school is under a cloud of an NCAA investigation and other scandals after its worst season since Carroll's first year. Although the charismatic 58-year-old coach spoke glowingly of his "gorgeous" tenure in Los Angeles, he jumped at the best — and timeliest — of many offers he's received over the years to return to the NFL, which he reveres as "the highest level of competition."

"I do not expect to ever be able to top what we just did," Carroll said. "I think it's just been a beautiful time together. It hurts to separate right now ... but it can't keep on going, because I can't pass up this opportunity."

Carroll's departure ends one of the most successful runs in college football history — perhaps right when it was about to become much less fun, considering the just-completed 9-4 season which ended USC's run atop the Pac-10 and snapped its string of BCS bowl games.