Less weight means more mobility for USC quarterback Matt Barkley

Here’s the skinny on USC quarterback Matt Barkley:

The sophomore’s loss of 10 pounds has made him more agile this spring. It is evident on rollouts and especially in the pocket, where the 6-foot-2, 220-pound Barkley has eluded pressure much better than he did last season.

“It’s nothing big,” Barkley said after practice Thursday. “It’s not like you’d see me on one of those commercials on TV, before and after.”

Barkley’s mobility was on display again as the Trojans reached the one-third mark of spring workouts. Showing no ill effects from off-season wrist surgery, he completed several high-velocity passes on the run and connected with a variety of receivers, tight ends and running backs on scoring passes.

“He’s forcing a few too many balls but I think he’s really picking up the offense,” Coach Lane Kiffin said. “The thing that I’m most pleased about is when you’re in the huddle with him, you can give him about half the play and he can finish the play for you. That’s what the really good ones do.”

Barkley said he spent much of last spring studying his playbook in the library late at night. Comfort now with the offense has enabled him to assert himself more as a leader.

“I feel a lot more comfortable speaking out and saying stuff to guys,” he said.

Barkley is looking forward to Saturday, when the Trojans will scrimmage more formally than they did last week. Avoiding turnovers, he said, was his main goal along with “just decision-making in general,” including settling for shorter passes to backs.

“I’ll probably say that till we play UCLA in the fall,” he said.

Graf impresses

With third-year sophomore Matt Kalil sidelined because of a hip strain, redshirt freshman Kevin Graf took nearly every snap at left tackle.

Graf, 6-6 and 315 pounds, is the son of Allan Graf and the brother of Derek Graf, both former offensive linemen for the Trojans.

Graf played guard most of the first week, showing versatility for a line that has been thinned by injuries.

Quick hits

Tight end Blake Ayles did not practice because of a concussion, and safety Marshall Jones will sit out the rest of spring practice because of a neck sprain suffered last week, Kiffin said. Jones redshirted last season after suffering a neck injury. . . . Linebacker Jarvis Jones (neck) remains sidelined and the possibility of playing again for the Trojans “doesn’t look good,” Kiffin said.

gary.klein@latimes.com

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