Five questions for the New Year, No. 2

With the final days of the year approaching, we're taking a look at the five most pressing questions surrounding Lane Kiffin's Trojans in 2012. We'll unveil one each day this week, counting down from No. 5 Monday to No. 1 on Friday.

Question No. 5 covered the Associated Press preseason top 25. Question No. 4 covered NCAA-sanctioned scholarship limits, and question No. 3 went over the new Pac-12 offensive systems.

Question No. 2, then, is this: Who will replace left tackle Matt Kalil in 2012?

There are two obvious options to replace Kalil, who earlier this month officially declared for the NFL draft as one of two USC juniors to declare. The other, defensive end Nick Perry, has clear replacements in Devon Kennard and Wes Horton, who split time across from him this year.

The first option for Kalil's slot is Kevin Graf, a redshirt junior. He started all of last season at right tackle and did so with a fair amount of success. The second is sophomore Aundrey Walker. He lost out on a chance to win the starting left guard spot in fall camp but played some in reserve throughout the year.

There's a very good chance it's one of those two guys. Anyone else would be a huge wild card.

Who has the early upper hand? It depends on whom you ask.

Graf obviously has the edge in terms of experience, with 12 starts under his belt. He performed well in most of those games -- all except Arizona State, really. Walker was a quiet disappointment, as he was clearly the first-choice freshman at left guard entering into fall camp but lost out to Marcus Martin because of work-ethic issues.

He's listed at 375 pounds but said he was closer to 350 at most points of the season. Well, if he was at 350 this year, then you can bet that the Trojans' coaches would like to see him report to fall camp at about 340 next August, with the goal of getting to around 330 for games.

As offensive line coach James Cregg said many times last season, it's not that he's incredibly overweight. He's 6-6 and a big guy. But if he's going to man the left tackle spot against some of the speedy ends in the Pac-12 conference, he needs to be a bit lighter.

USC needs Walker to start next season, really. It's just a matter of whether he can handle the left side or if he'll have to play right tackle, moving Graf over. With Martin, Khaled Holmes and John Martinez entrenched in the middle of the line, those should be the only O-line changes.

Missing Kalil last season would have been devastating to USC's offense. But missing him next year shouldn't be so terribly bad if Walker fulfills his potential, and it also sets up for another year of continuity in 2013. If the line is chosen as expected, only Holmes would depart next offseason.

Check back Friday for question No. 1.