Each time he broke a USC record last season, Matt Barkley humbly acknowledged his place in a Trojans quarterback lineage that includes Heisman Trophy winners and leaders of national championship teams.

Now, Barkley is mulling whether to return for a final college season or join former USC quarterbacks Carson Palmer, Matt Leinart, Matt Cassel and Mark Sanchez in the NFL.

Barkley's place in USC history is secure because he has played through some of the most severe NCAA penalties ever imposed in college football.

But where does Barkley rank all-time among USC quarterbacks?

"I can't do it right now," Coach Lane Kiffin says, "because I think it's too argumentative."

Longtime college football broadcaster Keith Jackson agrees.

"Different players surrounding them," he says. "And, for some, different offenses."

No matter, says former Trojans All-American receiver Keyshawn Johnson.

He calls Barkley "the best ever to play here."

Agree or not, longtime Trojans observers universally acknowledge that Barkley is, as former coach John Robinson put it, "one of the most important" players in Trojans lore.

Barkley started as a true freshman before becoming the poised face of the program when the NCAA handed down sanctions that included a two-year bowl ban and three years of scholarship reductions. He has nimbly handled hundreds of interviews in the 18 months since and led the Trojans to a 10-2 f inish this season.

"We've never had a guy that deserves to ride off on the white horse as much as him," Robinson says, "just because of the circumstances."

Statistically, Barkley ranks behind Palmer and Leinart, both of whom spent five seasons at USC.

Last season, Barkley established a Pac-12 record for touchdown passes and a school record for completion percentage. He also set single-game USC records for touchdowns, completions, passing yardage and total offense.

But Barkley, a three-year starter, has never been voted to the first-team all-conference or All-America teams. He has not led the Trojans to a conference title, though USC would have played in the inaugural Pac-12 Conference championship game this season if not for NCAA sanctions.

Nor has he won a national title or been a Heisman finalist.

"It's not all about the Heisman," says former quarterback Paul McDonald, who led the Trojans to a national title in 1978 and now works as an analyst on USC radio broadcasts. "It's all about the rings. It's a little unfair for a quarterback, but that's the way it is."

By that measure, Leinart is the best.

He helped the Trojans to an Associated Press national title in 2003 and a Bowl Championship Series crown in 2004, when he won the Heisman. He was a Heisman finalist again in 2005, when he led the Trojans to the BCS title game.