McKnight gets call early, and often?

Pete Carroll’s announcement Tuesday that tailback Joe McKnight would start Saturday’s opener against San Jose State did not come as a shock. But the timing spoke volumes.

In three previous seasons with the current stable of running backs, Carroll never made a declaration so early in the week before the opener.

It is a clear sign that Carroll and new play-caller Jeremy Bates plan to give McKnight an opportunity to earn a larger share of the carries and touches this season.

“Joe has a whole variety of things he does,” Carroll said. “He has a wider spectrum than the other guys. . . . He can run routes like a wide receiver, catch the ball outside and can do things very well in the backfield.”

McKnight, who averaged 7.4 yards a carry last season, has started only two games, at Oregon State and in the 2008 Rose Bowl against Illinois.

“Just because you’re starting doesn’t mean you stop being focused and [playing hard],” he said after practice. “I’ve just got to stay on it.”

McKnight’s ascent to the top of the depth chart is attributable to good health and a more focused work ethic, coaches said.

McKnight concurred, and also cited the birth of a son, Jaiden, seven months ago.

“It’s made me mature a lot, made me the person I am right now,” McKnight said. “I’m more focused in what I’m doing and being more accountable.”

Said Carroll: “He’s more serious about his workouts and his habits and how he comes across. He’s not as giddy as he was as a younger guy.”

Stafon Johnson, USC’s leading rusher the last two seasons, said he wasn’t disappointed McKnight would start Saturday. McKnight, Johnson, Allen Bradford and C.J. Gable are expected to share the workload. “I have no problem with that,” Johnson said. “It all depends on what happens at the end of the year. More power to him. He’s worked for it.”

Corp staying

Carroll’s decision to start freshman Matt Barkley at quarterback, and the prospect of Barkley’s holding the position for the next three years, will not cause Aaron Corp to transfer.

“I’m staying,” Corp said. “No question. I’m staying.”

Corp, a third-year sophomore, was No. 1 on the depth chart before he suffered a broken left fibula. He said he remained comfortable at USC and would continue to compete for playing time.

“Historically, guys who transferred, I think Troy Aikman is like the only guy that it’s worked out for,” Corp said.

Aikman transferred from Oklahoma to UCLA and was the top pick in the 1989 NFL draft.

Mitch Mustain, who started eight games for Arkansas as a freshman, transferred to USC in 2007 and is No. 3 on the depth chart. He said he was not surprised by Carroll’s choosing Barkley and that he would continue to work with the hope of receiving an opportunity.

“Who knows what will happen?” Mustain said.

Asked if he thought he made the right decision transferring to USC, Mustain did not hesitate.

“Yeah, absolutely,” he said. “I was in a program and played and what-not and it wasn’t a whole lot of fun. When you’re not learning, when you’re not improving, even when you’re winning games . . . it’s not a whole lot of fun.”

Quick hits

Cornerback Shareece Wright, who was declared academically ineligible Monday, said he’ll return next season.

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