USC’s Christian Rector breaks hand, which will require surgery

USC linebacker Christian Rector, who started the season as a backup before becoming the Pac-12 Conference’s sack leader, has a broken hand and will require surgery that will sideline him for multiple weeks, coach Clay Helton announced Thursday.

The injury further weakens USC’s already thin defensive front seven and pushes the Trojans closer to the point where the number of injuries would require major positional juggling.

Helton said that Rector is “probably weeks out” from a return. “We’ll see how that goes after the surgery,” he said.

USC could get some help at the “predator” linebacker position from Porter Gustin, whose own injury in Week 3 elevated Rector to the starting role in the first place. Gustin has missed five games with a fractured toe and torn biceps but was a limited participant in practice Thursday and will be a game-time decision Saturday against Arizona State.

Even if Gustin is cleared, he won’t be available to play a significant portion of the game.

“I don’t think that’s realistic,” Helton said. “If he’s capable, then it’ll be probably somewhere in 15 to 20 plays. If doctors are good, he’s good.”

USC has shifted inside linebacker Jordan Iosefa to the predator position, and Connor Murphy and Oluwole Betiku Jr. will also be available.

USC had just begun its “no-pads-November” practices a week early in an effort to halt a run of injuries that has left both sides of the ball beleaguered and thin. Despite playing in just helmets and shoulder pads, injuries found USC anyway.

Rector walked off in the middle of Wednesday’s practice accompanied by trainers.

He will become the 12th USC starter to miss a game because of injury this season.

“We’re one or two injuries away from being really limited,” Helton said.

Defensive tackle Josh Fatu participated in parts of practice Thursday for the first time since sustaining a concussion more than a week ago and will be a game-time decision, Helton said.

Fatu, who anchors USC’s front seven, was involved in a car accident last week and had not played since.

“Fatu got a little bit of work, moved around, looked good,” Helton said. “We’ll see again tomorrow and then make a game-time decision there.”

Freshman Brandon Pili started in Fatu’s absence against Notre Dame.

Helton does not expect running back Stephen Carr or tight end Josh Falo, who each have foot injuries, to be available against Arizona State. … Right tackle Chuma Edoga returned to practice Thursday after missing Wednesday’s practice with a stomach bug.

zach.helfand@latimes.com

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