USC backup quarterback Jesse Scroggins has hand surgery

If Matt Barkley were an ironman, it might not be an issue.

But injuries sidelined USC’s junior quarterback for a game in each of his first two seasons and the Trojans lost both games.

Finding a capable replacement, therefore, is paramount for the Trojans as they prepare for their Sept. 3 opener against Minnesota.

On Thursday, that competition took a major turn when redshirt freshman Jesse Scroggins underwent hand surgery for an injury suffered in a scrimmage on Monday. Scroggins did not practice Tuesday or Wednesday because of thumb discomfort in his right (throwing) hand.

Coach Lane Kiffin knew Scroggins was scheduled to see a hand specialist but did not anticipate surgery.

“It was a surprise,” Kiffin said of the procedure. “We did it quick for obvious reasons. But as of [Wednesday] I did not think that it was going to be that severe.”

Kiffin did not provide a timeline for Scroggins’ return, but the injury could turn out to be more than a tough break for the former Lakewood High star.

Scroggins might have suffered more than any other player from NCAA sanctions that prevented the Trojans from playing in a bowl game last season. Had the Trojans been eligible, he would have had 15 practices to take multiple first-team snaps, experience that might have allowed him to truly distance himself from freshmen Cody Kessler and Max Wittek, who each enrolled at USC in January to take part in spring practice.

Scroggins seemed to be ahead of both at the end of spring workouts, but the freshmen appeared to have closed the gap since.

Now they have a chance to move ahead.

“They don’t look like freshmen,” Kiffin said. “But, then again, this isn’t the real thing either.”

Kessler, from Bakersfield Centennial High, and Wittek, from Santa Ana Mater Dei, sense the opportunity.

“You can’t change your mentality, because once you start thinking about other stuff it will change your game,” Kessler said. “That puts a lot more pressure on yourself that you don’t need.”

Kessler got most of the opportunities in the scrimmage on Monday, passing for three touchdowns, with one interception that was returned for a touchdown.

Wittek, who threw only six passes, will have an increased role when USC scrimmages again Sunday at the Coliseum.

“I have a much better comfort level with the playbook and that has allowed me to play a lot more comfortable, without having to think so much,” Wittek said. “I can react instead of thinking.”

Leader of the pack

Brandon Carswell, perhaps the most consistent receiver during training camp, appears to be carving out a significant role.

The fifth-year senior, who bypassed a chance to leave the program after NCAA sanctions were handed down, also has emerged as a team leader.

On Thursday, after coaches announced that practice would conclude without what has become routine post-workout conditioning, Carswell reminded the players and coaches that it was necessary for the team to finish.

After the Trojans completed a series of sprints, Kiffin and several players praised Carswell for speaking up.

Quick hits

One week into training camp, minor injuries are starting to mount. Receiver Robert Woods (ankle) and linebacker Dion Bailey (foot) were among the players who sat out Thursday. ... Sophomore Markeith Ambles, a receiver who had been held out of practices to focus on classwork, was on the field but wore a white defensive jersey without a number and worked with the defensive backs.

gary.klein@latimes.com

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