Freshman CB Seymour in the mix already

Six days from Sunday, USC will line up against Norm Chow's Hawaii offense in a sold-out Coliseum and kick off the 2012 season.

By now, almost everything's all set for the opener. One of the last remaining unknowns is who Matt Barkley's backup will be, and it now appears that will become known on Tuesday.

But there is still one critical position that's still technically undecided: Nickel corner, where nobody has clearly emerged behind Nickell Robey and Anthony Brown to be the go-to guy.

The most likely candidate is freshman Kevon Seymour (pronounced with an emphasized "key"), who's been running with the second-team defense in practice for much of camp and has also taken on nickel-back duties of late. A local kid from Pasadena Muir High, Seymour was viewed as a top prospect who could redshirt due to the Trojans' overall defensive-back depth.

But because of Isiah Wiley's academic ineligibility and camp injuries to older, more experienced players, Seymour has stepped into the nickel role and looked reasonably ready. He's going to be USC's third corner against Hawaii unless something drastic happens this week.

"I'm not surprised," Seymour said Sunday in his first collegiate media session. "I've been working hard and doing everything I can, getting in my playbook.

"I make a few mistakes here and there, but I make sure I go back to my playbook later on that day and fix that mistake I made."

One critical element that works in Seymour's favor is his size. USC's two starting corners will be 5-8 and 5-9. It'd be nice to have a 6-footer on the field every few snaps to prevent the same size mismatches from being exploited too often.

He's also benefited from defending Robert Woods and Marqise Lee on a daily basis. That's naturally sped up the progress he's made in the two months since he graduated high school.

"I didn't see anything like that in high school," Seymour said. "I won't be so nervous (against Hawaii) because in practice I go up against the best receivers and the best guys."