Nose tackle Antwaun Woods underwent surgery after injuring a pectoral muscle last week and will be sidelined for the Dec. 27 game at Qualcomm Stadium in San Diego, Coach Steve Sarkisian said Wednesday.
On Tuesday, Woods posted to Twitter an Instagram photo of himself in a hospital bed. He attended Wednesday's practice but players were not made available to the media. His left arm will remain in a sling for about six weeks, Sarkisian said.
Woods, a junior, has started 10 games. He has 37 tackles, including a sack.
The Trojans have several options for replacing Woods.
Cody Temple has played the spot and tackles Delvon Simmons or Claude Pelon could move to the nose position. Leonard Williams also could play there, Sarkisian said.
Nebraska features running back Ameer Abdullah, who has rushed for 1,523 yards and 18 touchdowns, and quarterback Tommy Armstrong Jr., who has run for five touchdowns.
"We have to be prepared for both guys running the football right at us," Sarkisian said.
After taking several days off to focus on finals, the Trojans resumed practice with a performance Sarkisian described as "extremely average."
"Today wasn't good enough," he said.
Sarkisian anticipated that players might not be quite as on point on the field.
"You prepare for it, but you never want to accept it," he said. "And they understand it. I expect us to be much better," Thursday, he said.
Before Wednesday, USC had gone through six developmental practices in which younger players took extended first-team reps.
This week, the Trojans will install their game plan for Nebraska.
USC will practice Thursday, Friday and Saturday before taking two days off. They return to practice on Tuesday and then depart that afternoon for San Diego.
Williams collecting honors
Williams was selected first-team All-America by the American Football Coaches Assn.
Williams, a junior from Florida, was previously announced as a first-team All-American by ESPN.com and Fox Sports.
Williams was a second-team selection by the Associated Press and the Walter Camp Foundation.
Williams, 6 feet 5 and 300 pounds, is regarded as a top NFL prospect and is expected to make himself available for the 2015 draft. He has 8 1/2 tackles for losses, including six sacks, and has intercepted a pass and forced three fumbles.
It's been a steady stream of postseason recognition since Williams missed being named to the Walter Camp first team. The night the team was announced last week, Williams posted "Disappointed" to his Twitter account.
"I understand why I was on the second team," he said the next day. "I was just more disappointed in myself and my stats. ... It was just a reflection on me. I never want to blame other people."
Browne staying ready
Cody Kessler is taking the majority of first-team snaps, but backup quarterback Max Browne continues to get opportunities.
"We're just pushing Max to not get comfortable, not accept his role and to prepare and practice as if he's the starter," Sarkisian said. "It's a hard thing to do as a backup 13 games into the season, but he's a really mature guy who understands it.
"He pushes himself. He works just about as hard as anybody on our roster. ... He works at his craft."
Tailback Tre Madden, who has not played this season because of a toe injury, rode an exercise bicycle during the workout. Linebacker Uchenna Nwosu, who suffered an ankle injury last week, did not practice and wore a protective boot.