USC leading rusher Vavae Malepeai to undergo knee surgery

USC's leading running back Vavae Malepeai is set to undergo surgery to "clean out" whatever is causing persistent pain and swelling in his knee, coach Clay Helton announced Sunday night.

Helton did not have a timetable for how long Malepeai would be sidelined.

The redshirt junior, who has a team-high 87 carries for 406 yards and 4 touchdowns, has been playing through the knee pain for several weeks and the hope was that the Trojans' bye week would provide him enough rest to move forward with it.

He had 8 carries for 46 yards and 1 catch for 9 yards in USC's 30-27 loss at Notre Dame on Saturday night.

"Vavae's knee has finally gotten to a point with the swelling that medically they're going to go ahead and clean it out," Helton said. "... Vavae's a warrior and has been dealing with a sore knee and really fighting through it for his team and it's just gotten to the point where it's gotten too sore so we're going to go ahead and take care of it now. The good fortune is we've still got a lot of talented backs on this team."

USC's top rusher Saturday night was redshirt freshman Markese Stepp, who rumbled for 82 yards and a touchdown while matching his season-high with 10 carries.

Stepp leads the Trojans overall at 6.9 yards per carry this season, turning just 35 touches over four games into 241 yards and 2 scores. Saturday night marked the first game he's led the team in carries outright, after tying for the team lead with 10 carries against Washington as well.

Junior Stephen Carr is averaging 5.8 yards per carry with 233 rushing yards and 2 touchdowns on the ground in addition to 15 catches for 103 yards and a score.

Stepp and Carr would form an intriguing one-two punch with their demonstrably different skill sets -- with Stepp the bruiser 235-pound rusher who seems to create extra yards after contact on every play and Carr the change-of-pace pass-catching threat out of the backfield.

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Behind them is veteran Quincy Jountti, a former walk-on who was put on scholarship in August, and speedy true freshman Kenan Christon, who has yet to play in a game. Christon -- a state-record-setting track star from San Diego -- traveled with the team and dressed for the game Saturday, but did not see any action. Thus, he can still play in four games without burning his redshirt season, and it seems likely he'll get an opportunity at some point in the coming weeks.

"We've been very fortunate here to garner a lot of talented backs, Vavae being one of them. Stephen Carr, Markese [Stepp] and we have Quincy Jountti as well as Kenan Christon," Helton said. "So the beautiful thing about the new rule is with four games and still being able to redshirt is it allows you to play some freshmen and still have the decision whether you redshirt them or not and Kenan's in that position. So we still have a bunch of talented backs."

Helton rattled off the rest of USC's injury report coming off the Notre Dame game, but he didn't have status updates for those players regarding their expected availability for next Saturday against Arizona.

"There was a bunch of kids that I just thought were warriors. They suffered injuries in the game and went back out there and battled," Helton said.

-Linebacker Palaie Gaoteote sprained his ankle but returned to the finish the game.

-Nickel Greg Johnson suffered a shoulder injury that forced him out.

-Cornerback Olaijah Griffin's "back acted up again and that pulled him from the game," Helton said. Griffin had missed the previous game due to back spasms/bulging disk.

-Fellow cornerback Isaac Taylor-Stuart suffered an ankle sprain but was able to return and finish the game.