Practice No. 13 tidbits + video

Two main stories out of USC's Tuesday practice: Matt Barkley is growing frustrated this spring with the Trojans' lack of depth at receiver and on the offensive line, and the injuries are also starting to mount, across the board. Here's the rest of what went on at Howard Jones Field on Tuesday, with more coming on injured cornerback Tony Burnett on Wednesday:

Ambles late, again

Sophomore receiver Markeith Ambles went approximately two practices without getting in trouble. The talented Georgia product again found himself doing individual drills on the sidelines during Tuesday's early-morning practice after he showed up late to pre-practice meetings Tuesday.

This after Ambles skipped a scrimmage at the Coliseum earlier this month and showed up late to multiple other team functions preceding that, and then apologized last week at practice for what he said was a misunderstanding and returned to practice fully on Thursday.

"There were two guys late for meetings this morning," Kiffin said. "And so both of them ran."

The other player was walk-on quarterback Brett Kan, a 2010 transfer from Princeton who has no history of off-field trouble at USC.

Practice highlights

Most of the best plays of the day were made by sophomores Nickell Robey and Robert Woods. Robey had two big-time plays Tuesday, first knocking the ball away from Woods in a memorable battle between the two and then picking off Max Wittek's pass, also intended for Woods, and taking it back the other way.

Woods managed a sweet, juggled catch on the sidelines at Howard Jones Field and made several more grabs.

Other highlights included a surprise appearance by former USC receiver Keary Colbert, who practiced with the team sans helmet and pads wearing his old No. 83 and looked fairly speedy running routes against the current Trojans.

Colbert stepped down from his position as tight ends graduate assistant for the team earlier this year to pursue an NFL comeback.

Spring game notes

Lane Kiffin's first spring game at USC saw roughly 15,000 people come out to the Coliseum to watch the Trojans battle the Trojans. His first -- and only -- at Tennessee? 51,000.

That's the difference between the Pac-10 and the SEC, Kiffin said Tuesday, in explaining why USC's spring game, scheduled for Saturday at 1 p.m. at the Coliseum, won't be televised this year.

"It’s different in the South and being out here," he said. "It just is what it is. We have 51,000 at Tennessee for our first spring game, and there were 40,000 there two hours before for the walk. It doesn’t make it good or bad; it’s just very different.

"If you look at the games being telecast on the bigger networks, I think you’re going to find basically the Big 12 or the SEC."

USC's game will be broadcast live on 710 ESPN radio in Los Angeles, and the school's official RipsIt blog will also have some sort of live coverage to speak of, but it pales in comparison to schools like Oregon and Texas, both of which had their spring games televised and highly-attended.