Will it be Walker or Tuerk?

LOS ANGELES -- USC coach Lane Kiffin didn't really hide his displeasure with left tackle Aundrey Walker after the Stanford game, saying Sunday he was going to give freshman Max Tuerk repetitions at the starting left tackle spot this week to open up the competition there.

Tuesday, Kiffin opened up about why Walker was being challenged for his starting job but expressed confidence he would retain it.

"We won't tolerate (a) lack of great effort," Kiffin said. "Not when you put on these jerseys that all these great players have worn before.

"I think Aundrey's going to respond well to this."

Walker's effort in the fourth quarter against the Cardinal was clearly subpar. He can be seen on tape standing as a defender passes him by multiple times, and that clearly didn't go over well with Kiffin or offensive line coach James Cregg.

Kiffin said Walker was doing alright earlier in the game, before Stanford took the lead and he began to tire.

"He actually had a pretty good first half," Kiffin said. "And then the second half didn't play as well as we'd like, performance-wise and effort-wise."

Asked Tuesday if he felt he gave a good effort in the second half of Saturday's game, Walker smiled.

"I'm going to leave that behind me," he said. "That game is in the past. I'm just looking forward to this week."

Tuerk took over at left tackle in fall camp when Walker was out because of an injury and seemed to improve daily. But, at 6 feet 6, 275 pounds, he's considered small and inexperienced for the college level.

He has been noted to give great effort, though.

Kiffin said Tuesday it was "too hard to make a judgment without going back through the film" of the competition between Walker and Tuerk.

"But we're looking for finish, great effort," he said. "Guys are going to get beat. Guys are going to drop balls, just like we told our team Sunday: You're going to make mistakes."