USC has been showered with gallons of preseason accolades. It was picked to win the Pac-12, it was picked to play for the national championship and quarterback Matt Barkley was picked as a Heisman Trophy favorite.

One coach who is extremely familiar with the program even ranked the Trojans No. 1 in his preseason poll.

But before the Trojans achieve those lofty goals, they’ll have to sort out their depth chart, including choosing a backup QB between Cody Kessler and Max Wittek. It's a nice little storyline, but we prefer to focus on three battles for starting positions.

Nose tackle: Antwaun Woods vs. J.R. Tavai
Tavai played in seven games as a backup last year and has the early edge. He’s quick, but he’s only 6-feet-2 and 270 pounds and may struggle against the run. Woods (6-1, 315) is a promising redshirt freshman and has the perfect build to eat up space at this position. He needs to improve his conditioning.

Left guard: Marcus Martin vs. Cyrus Hobbi
Martin started the final 10 games of 2011 and has prototypical guard skills. He’s strong at the point of attack, stays with plays and likes driving linemen off the ball. But he’ll have a major challenge on his hands from highly touted redshirt freshman, Hobbi, from perennial power Saguaro (Ariz.) High. At 6-foot-3 and 295 pounds, Hobbi is already approaching NFL size. He played well in spring ball, too.

Left defensive end: Greg Townsend Jr. vs. Morgan Breslin vs. Leonard Williams vs. Kevin Greene
A torn pectoral muscle could sideline expected starter Devon Kennard for the season, opening the door for an unexpected player. Townsend is a redshirt freshman, Breslin is a junior-college transfer, Williams is a true freshman and Greene is a redshirt junior. The bet here is that D-line coach Ed Orgeron uses a rotation. Townsend (6-3, 260) and Williams (6-5, 270) have similar size and could be first and second down players, while the smaller, faster Breslin (6-2, 245) serves as a pass-rush specialist.

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