COLUMBUS, Ohio - His throwing shoulder numb, his team's national championship hopes at the brink, Matt Barkley jogged into the USC offensive huddle and explained the moment.

Seven minutes left, he told his teammates. Five points down to the host Buckeyes. Eighty-six yards of field separating them and an enormous sigh of relief.

And then, the true freshman quarterback, college football's newest Johnny Bravo, did something remarkable.

"He just smiled," receiver Damian Williams said.

In 53 minutes of pre-smile football, No. 3 USC had gained 229 yards, and its offense had scored one touchdown. In the night's final seven, the Trojans slapped together an 86-yard drive and tallied a second touchdown, the difference in an 18-15 victory over No. 8 Ohio State.

What changed? Nothing in the scheme, Barkley and his teammates said. Nothing about his poise and composure and maturity, the stuff about which they've raved since the kid got to Troy. Ohio State's defense, a stalwart so far, didn't shake up much either.

No, all that changed is that Barkley began to emerge as a great one. He completed a pair of third-down passes, converted a pair of quarterback sneaks, and led the most important USC rally this side of the Bush Push.

Afterward, the raving continued.

Said offensive lineman Jeff Byers: "The kid's incredible. I can't think of anything more incredible to do than, you're a freshman, and you lead a winning drive in the Horseshoe."

Said linebacker Chris Galippo: "He played so not like a freshman. I don't know if anyone — (Mark) Sanchez, (Matt) Leinart, Carson (Palmer) — I don't know if anyone could have done it better."

Said USC coach Pete Carroll: "Let the games begin as far as talking about his career."

For a while, Saturday seemed like it would be a forgettable part of that career. Barkley was 12-for-26 for 140 yards before taking the ball with 7:15 remaining. He banged his shoulder taking a late-third quarter hit and said it bothered him the rest of the way.

"Hurt every throw," he said. "But it didn't limit me."

The boy wonder started his fateful drive by taking a sack to set up second-and-14. Then a false start made it second-and-19 at the USC 5. But, as his coaches and teammates predicted, he never panicked.

He got help from Joe McKnight, who finally strung together a big game at a big time (105 total yards), and from a defense that kept the Buckeyes to 265 yards.

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When it was done, as an assistant trainer wrapped an ice bag on his shoulder, it dawned on him that his work wasn't done. USC had games like this before, seen heroes like this before. And then the Trojans have slipped — Oregon State last year, Stanford before that — and made the September magic moot.

"This is the best thing that could have happened to Washington," Carroll said of his team's next opponent. "That maybe we'll get all caught up in the glow of this win. I've already addressed the guys about it."

But maybe, some Trojans said, this group will be different. It's already got a different quarterback, they say. A different finish, an undefeated finish, might be ahead, too.

And if that's the case, Barkley can smile all the way to a national championship game.

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