USC middle linebacker Oscar Lua made his initial mark with the Trojans as a special teams standout in 2002.
With top-ranked USC coming off a terrible performance in kickoff coverage against Arizona -- and with ninth-ranked Notre Dame up next -- Coach Pete Carroll on Wednesday returned Lua to his special teams roots.
"It was inevitable," said Lua, a fourth-year junior who is the Trojans' leading tackler. "The kickoff team is struggling a bit, so they need some sort of leadership out there.
"So I'm just going to go out there and provide something like a mentor role and just show them how to get it done I guess."
Arizona's Syndric Steptoe returned five kickoffs for 159 yards against the Trojans and might have scored a touchdown had he not tripped on a 76-yard return.
Carroll said younger players have been filling special teams roles usually held down by veterans because of depth issues caused by injuries. He said he moved Lua back to the unit "to shore us up a little bit with a little more experience."
Lua, who sat out the 2003 season because of a knee injury, said the extra special teams responsibilities would not drain him.
Linebacker Thomas Williams, who also made his mark on special teams, said he told coaches he would be ready if called upon.
"Our coverage team needs all the help they can get," he said. "It's kind of my bread and butter from the beginning."
Running back Reggie Bush participated in the full workout with a sleeve made of synthetic rubber protecting his bruised right knee.
After practice, Bush dashed across the field to a supply cart, sat on the flatbed portion and got a lift to the locker room.
"I'm just getting a ride," he said, laughing. "I'm fine, 100%."
Freshman linebacker Brian Cushing, who feared that a shoulder injury would force him to sit out as a redshirt, was cleared by doctors and practiced with an eye toward playing against Notre Dame.
Cushing, a New Jersey native, chose USC over Notre Dame.
"The will of Cushing, with this Notre Dame matchup and trying to get back closer to home was pretty strong," Carroll said. "He healed himself."
Cushing said his left shoulder remained "a little weak," but that he was happy to practice after being out for four games. Cushing opened the season second on the depth chart at the strong-side spot behind senior Dallas Sartz, who has sat out three games because of a shoulder injury and will probably have surgery and become a redshirt.
Sartz's father, Jeff, said Tuesday that it was "99%" his son would be a redshirt.
Sartz dressed but did not participate in drills Wednesday. He said he would make a final determination about his status at the end of the week.
Carroll said, "This is Dallas' shot and he's not making it. There's a real good chance this will put us in position to redshirt him."
Former All-American defensive tackle Mike Patterson, now with the Philadelphia Eagles, former safety Jason Leach and former cornerback Kevin Arbet attended practice.... Safety Kevin Ellison and cornerback Terrell Thomas each had reconstructive knee surgery and are expected to be out nine months, a USC athletic department official said.