The Colorado Buffaloes showed rare rhythm on their opening drive, marching down the field and taking an early lead.

Only one problem: "About 58 minutes left," coach Jon Embree said. "Seven points wasn't going to be enough."

Especially not with Matt Barkley running the show. Barkley torched the banged-up Buffaloes for a school-record six touchdowns to lead No. 21 Southern California to a 42-17 win on Friday night.

The Buffs (1-9, 0-6 Pac-12) have faced quite a few elite quarterbacks in their first foray through the conference, and Barkley, who's just a junior, ranks right up there. He was on target all game, finishing 25 of 39 for 318 yards.

"That's why he needs to leave next year," Embree said, chuckling. "That's why he needs to go."

To the NFL, that is. The USC faithful serenaded Barkley after the game with chants of "One more year."

The Buffaloes went with a different look against USC (7-2, 4-2) in an effort to change their luck.

It didn't work as they lost their seventh straight.

Barkley and the Trojans were simply that good. This conference, in general, has been that good. Colorado has been outscored 266-91 in its first year in league play.

"It hurts," said junior defensive end Will Pericak, whose team was decked out in black helmets for only the second time ever and the first time since 1998. "Guys are hurting — it's their senior year and we haven't pulled out a win at home."

Just one more chance remains to fix that at Folsom Field — against Arizona next weekend. And there, the Buffs will face yet another talented quarterback in Nick Foles.

Colorado has seen a steady stream of elite QBs this season. Heisman Trophy contender Andrew Luck of Stanford threw for 370 yards and three scores against Colorado, while Keith Price of Washington roughed up the Buffs for 257 yards and four TDs.

But Barkley may have turned in the top performance, picking apart the secondary as he threw two TD passes to both Marqise Lee and Robert Woods, another to Xavier Grimble and the record-setting one to Amir Carlisle.

Oh, and Barkley saved a score as well.

Jason Espinoza picked off an errant pass just before halftime, only to have Barkley make a touchdown-saving tackle at the 8.

"I'm kind of mad I didn't score, but that was only my second play of the game," said Espinoza, who saw his first action since suffering a concussion at Washington on Oct. 15. "My legs were a little cold."

That was about the only mistake Barkley made.

"It was awesome," Barkley said. "We knew their ends were rushing upfield petty fast and it was just a quick screen to him. He made some nice maneuvers and got in."

The Buffaloes received a boost on offense with receiver Paul Richardson (four games) and tailback Rodney Stewart (two games) returning from knee injuries. Stewart accounted for 155 yards of offense on 21 carries and six catches.

With that performance, Stewart surpassed position coach Eric Bieniemy as the school's all-time leader in all-purpose yards.

But that held little consolation.

"It's good to break a record, but it's not OK to lose," Stewart said. "I'm kind of down right now. I'm proud of myself, but at the same time we still have a lot of stuff we need to work on. The season is not over."

The Buffaloes came out blazing, moving the ball down the field before scoring on Toney Clemons' 37-yard TD catch. It was Colorado's first lead in more than 244 minutes.

But it didn't last long. The Trojans tied it up on Lee's 33-yard TD catch when he beat Colorado cornerback D.D. Goodson, who was a tailback until a few weeks ago when he was moved to the other side of the ball bolster a battered secondary.

After that score, the Trojans were off and running.

And the Buffaloes were left hurting. They were already without their top three tacklers in Anthony Perkins (ankle), Douglas Rippy (knee) and Ray Polk (concussion).

Then they lost starting linebacker Brady Daigh (wrist) and strong safety Kyle Washington (concussion).

"Tough one," said Embree, whose team also had two field goals blocked. "I felt like the way we came out, we played with good intensity and energy, but they wore us down. We didn't have enough."

Notes: Clemons had a career-best game, finishing with five catches, 112 yards and two TDs. .... Colorado QB Tyler Hansen had 295 total yards, which gives him 5,476 in his career. He moves into fifth place in school history, passing Koy Detmer.