Some positions on defense still are up for grabs

Fall-semester classes have begun at USC, so the Trojans will resume practice Tuesday with a new schedule that features 7:45 a.m. workouts.

It’s still too early to tell if the wake-up call that the defense received in 2010 has been answered.

During training camp, the USC defense looked bigger, faster and less confused than it did a year ago, when the unit ranked 84th among 120 major college teams.

However, the last two weeks were spent going up against the Trojans’ mostly traditional pro-style offensive scheme. Many of USC’s opponents run variations of a spread attack.

Coach Lane Kiffin said the defense “suffers” because it “wastes a lot of camp time” stopping plays that are run out of formations the unit might not see.

“And then everybody else comes in here and spreads you out,” he said. “So we’ve got to move in that direction.”

The Trojans will begin preparing for a Minnesota offense that features quarterback MarQueis Gray, a 6-foot-4, 240-pound junior who is a converted receiver.

Several starting defensive positions for USC are still to be determined.

Senior Chris Galippo will start at middle linebacker. But Shane Horton, Hayes Pullard, Dion Bailey and Marquis Simmons appear to still be competing for two outside spots.

During Sunday’s scrimmage at the Coliseum, sophomore Demetrius Wright and junior Jawanza Starling alternated as first-team safeties opposite starter T.J. McDonald. And junior Drew McAllister continued to show playmaking ability by intercepting a pass for the second consecutive scrimmage.

Cornerback Torin Harris also intercepted a pass for the second scrimmage in a row, improving his bid to start opposite Nickell Robey.

Will the Trojans tackle better this season?

The Trojans have improved, Kiffin said, but added that “until a real game happens ... where they get people out in the open field, that’s when we’ll really know.”

Early returns

Robert Woods will return kickoffs and Robey appeared set to return punts.

But Robey muffed a punt that resulted in a lost fumble in Sunday’s scrimmage. He then returned a fumble for a touchdown on the ensuing possession.

“That was a mistake on my end, just trying to make a play on the ball,” he said of the punt. “The game goes on, you have to forget about it and keep moving on.”

Kiffin, however, indicated that the punt-return job might remain open.

“The No. 1 thing is going to be catching the ball,” Kiffin said.

Quick hits

Receiver George Farmer is expected to return to practice after being held out of the scrimmage because of a concussion. ... Quarterback Jesse Scroggins, who was removed from the 105-player training-camp roster because of a thumb injury, is eligible to return to practices and meetings because school has started and rosters can be expanded.

gary.klein@latimes.com

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