Stephen Carr takes USC’s defense for a spin

Stephen Carr, USC’s freshman running back, took an inside handoff during Saturday’s practice and dashed to his left. Then, with one hard plant, he wasn’t going left anymore, though USC’s first-team defense still was, as if it was playing on ice.

Carr reversed field and scampered easily into the end zone. He’d score again, also on a big cutback and had another would-be touchdown negated by a holding penalty that was incidental to the play. The last was set up the same as the first two: with a single, firm plant.

Carr was one of the jewels of USC’s latest recruiting classes, and he flashed why Saturday. USC ran its first live-action practice of training camp, and coach Clay Helton opted to rest starting running back Ronald Jones II for most of the 50 to 60 full-contact plays.

Helton said he wanted to see what the next options at running back would bring. What he saw was a young tailback that looked a lot like Jones.

“I think he’s got great vision,” Helton said of Carr. “He reminds me a little bit of RoJo that I have no idea where he’s going. But those special players like a Ronald Jones at running back, like a Sam Darnold at quarterback, they see things that others don’t.”

Carr, 6 feet and 210 pounds, has carved out an early role in a crowded backfield. Aca’Cedric Ware entered training camp as Jones’ primary understudy. Vavae Malepeai drew rave reviews from coaches last season, his first year in the program, but was a redshirt after an injury. Helton said he will use Malepeai in short-yardage situations.

Carr, though, has the potential to be a featured running back.

“He truly puts one foot in the ground and is able to transition in another direction,” Helton said. “Really good day by him.”

Tyler Vaughns moves up

Tyler Vaughns has practiced with the first-team offense during the beginning of training camp, and on Saturday, he made a difficult, contested catch over cornerback Iman Marshall in the end zone.

There are few true positional battles this training camp. Receiver is one of them. Deontay Burnett is a lock to start. Jalen Greene has also played with the first team.

“One of the things that you see from Tyler that I like is he’s really making the tough catches,” Helton said. “To go against one of our better corners on our team in Biggie and to be able to go up and make that play, that tough catch, that’s what we’re looking for.”

Helton said he showed the entire team clips of difficult, gave-saving catches from Darreus Rogers and JuJu Smith-Schuster from last season. He told his receivers that winning a starting role would require similar catches.

“Really hope there’s not a production drop from last year,” Helton said. “It’s going to take some work.”

Quick hits

Helton said Saturday was “without question” Darnold’s best performance of training camp. “I thought he was really, really good,” Helton said. “Protected the ball well. He took what was there. His feet were extremely active in the pocket. There was no laziness.” … An MRI exam found no structural damage in tight end Josh Falo’s injured knee. He was diagnosed with a bone bruise and is expected to sit out about a week. … Tight end Tyler Petite was out in concussion protocol. … Safety Marvell Tell III was held out because of hamstring tightness.

zach.helfand@latimes.com

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