Starting center Khaled Holmes has not participated in camp since acquiring an injury during the first practice (Neon Tommy).

USC's first day in shoulder pads didn't go quite as planned for the offense. In addition to facing what is considered to be one of the top defenses in the country, the Trojans’ offense was also without two of its starting offensive linemen. Returning starter Khaled Holmes has been out since going down the first day of camp with an ankle injury, and joining him today was projected starting left tackle Aundrey Walker. Neither the type of injury Walker sustained, or the severity of either injury, is known, as USC no longer discusses injury information.

FRESHMEN MAKING AN IMPACT IN THE TRENCHES

It's noteworthy for true freshmen to make an impression on coaches at any position, but along the offensive and defensive lines, it's even more impressive. The physicality and strength required to play in the trenches usually requires some time to adapt from college to high school. But defensive lineman Leonard Williams and offensive lineman Max Tuerk have drawn praises from coaches for standout performances thus far in training camp.

THE SEARCH CONTINUES

The search for a third wide receiver to join Marqise Lee and Robert Woods isn't going as easy as planned. George Farmer, who played part of last year at running back before getting hurt, and true freshman Nelson Agholor are the "favorites," but neither is seizing control of the position. That leaves redshirt junior De'Von Flournoy, who has been having a solid camp, after an impressive spring. Coach Lane Kiffin praised him for his efforts and it seems he leads the battle at that position. Agholor has been impressive, though. Once he learns the offense, should be a contributor for the Trojans this season.

WHO WILL BACK UP BARKLEY?

One position USC hasn't had to worry about for a few seasons now is the quarterback position. But with Matt Barkley entering his final season in cardinal and gold, the focus on the No. 2 quarterback has intensified, as the No. 2 this year would be the favorite to take over for Barkley in 2013. Max Wittek and Cody Kessler have been battling for the backup job since arriving on campus in spring of 2011 yet haven't been able to separate from one another. Kiffin says he plans to name a true backup by the time the season starts. For now, they will continue to split reps, and fight for the job.

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