A final exam awaits Christian Rector and USC’s emergency starters entering crucial stretch

Christian Rector sat on a dais next to USC Coach Clay Helton on Saturday as Helton declared that Rector is “becoming a superstar.”

Rector listened and shook his head.

The defensive utility man has played significant minutes only in the last four games, which makes him one of the keys to maybe the most important stretch of USC’s season: a game Saturday against Utah followed by a trip to Notre Dame.

Injuries have ravaged USC over the first half of the season, and fully half of the starting offense and defense have missed time. But the absence of starters has presented the team’s younger players and reserves with a rare opportunity for playing time. How well they capitalized on that playing time in the first half could determine whether USC can emerge from the second half with the Pac-12 South title.

No one has taken advantage as much as Rector, who saw major minutes starting in USC’s third game against Texas when outside linebacker Porter Gustin left with an injury. He has also filled in at times for defensive end Rasheem Green and rotated to the other defensive end spot on third downs.

He has used his time productively. He is tied for the team lead in tackles for loss (six) and quarterback hurries (three). In sacks (4.5), fumble recoveries (two) and forced fumbles (two), he leads the team.

“His availability to play multiple positions I think has really helped,” Helton said. “He’s one of those great examples that you love to use as a coach about, it doesn’t always happen for you sometimes in Year 1 or Year 2. You develop as a player.”

Rector probably would not have had a chance to show his disruptive abilities without injuries. Defensive coordinator Clancy Pendergast does not like to rotate players often. USC’s outside linebackers, Gustin and Uchenna Nwosu, are among the best in the conference. Likely, he would’ve remained primarily a third-down rusher.

Other players, such as receiver Tyler Vaughns, first won the starting job because of injuries. Vaughns led the team in receiving in two straight games and caught his first touchdown pass on Saturday. And Helton said freshman tight ends such as Erik Krommenhoek and Josh Falo have gained valuable experience because of an injury to tight end Daniel Imatorbhebhe. Falo caught his first pass, a touchdown, on Saturday.

USC’s most critical replacement is probably Andrew Vorhees, a freshman who has replaced Viane Talamaivao, who will miss the rest of the season with a pectoral injury.

Vorhees and a makeshift offensive line struggled against Washington State, but Helton said Vorhees “played a wonderful game” against Oregon State.

In the next two weeks, greater tests await him and the rest of USC’s emergency starters.

Close to returning

Imatorbhebhe says he is feeling no pain and is moving closer to a return from a hip flexor injury that has sidelined him for all but a few snaps this season. Helton had previously said that USC is planning on a return prior to a contest against Notre Dame, in two weeks.

“He said that was the goal, and if it’s before then it’s before then, and if it’s after then it’s after then,” Imatorbhebhe said. “It’s hard for me to see it being after then, considering how good I feel right now.”

Imatorbhebhe has begun running and will add to his workload this week. “I can do, basically, it all,” he said. “There’s not really anything I can’t do. Now it’s just getting my brain used to moving and not anticipating pain. Just getting used to running and stuff. That’s what I used this past week for. I’d imagine it’s going to ramp up even more this week, getting to do a lot of practice and stuff like that.”

Quick hits

Helton said right tackle Chuma Edoga (high ankle sprain) told him on Saturday, “Coach, I’m trying my hardest to get back this week.” He remains day-to-day. … Defensive tackle Marlon Tuipulotu and his family will meet with doctors this week to determine a plan for his injured back. Helton said surgery is a possibility. They will reach a decision by Tuesday. … Long snapper Damon Johnson left Saturday’s game with a back injury and was also put in concussion protocol. … Receiver Deontay Burnett injured his toe. ... USC moved up a spot to No. 13 in the Associated Press poll.

zach.helfand@latimes.com

Follow Zach Helfand on Twitter @zhelfand