UCLA quarterback Richard Brehaut puts in some time

UCLA quarterback Kevin Prince sat out practice for a second day because of back pain, leaving more time for backup Richard Brehaut with the first-team players.

Brehaut, who played in six games last year as a freshman, has looked sharp at times this week. Other times it was clear he is still on the learning curve.

But his improvement from a year ago has been noticeable to coaches.

“He knows what he is doing, at least most of the time,” Coach Rick Neuheisel said. “It was a 50% proposition last year.…He’s a fearless kid, but you can’t play this position without having all the tools. Knowing everything is certainly a necessary item in your tool box.”

Brehaut appeared to be rushed into his college career last season. He completed 11 of 17 passes from 124 yards in limited play. At times, he held on to the ball too long. Other times, he was unclear of the offensive scheme.

But offensive coordinator Norm Chow said, “It’s interesting what happens to college kids when they go from 18 to 19. He has shown some real maturity.”

Brehaut, meanwhile, has accepted his current status as backup after competing for the starting job a year ago, but said, “You’re still only one snap away from being in there.”

What Brehaut has learned is “to dedicate more time in the film room. I’ve been watching a ton of film and that has helped me with my anticipation.”

Brehaut has not contemplated the future, as he and Prince are both sophomores. Brehaut does have a redshirt year available and “there is no saying what I can do with that.”

For now, Brehaut said, “I just want to be ready to come in so the offense doesn’t miss a beat.”

Prince is expected to be out one or two more practices.

“We want that muscle to calm down,” Neuheisel said. “If you’re not healthy, you could rip it again throwing and then you’re back to square one.”

Triage

UCLA offensive lineman Jeff Baca is out indefinitely after learning he had a stress reaction in the fibula of his right leg.

Baca, a junior, underwent an MRI exam Thursday morning after persistent pain in the leg that started back at the end of summer training.

Freshman linebacker Aramide Olaniyan sat out practice after spraining his left ankle, which was immobilized with a boot. Linebacker Patrick Larimore sat out after “tweaking his hamstring,” Neuheisel said. He is expected to be back on the field in the next few days.

Let’s get physical

The Bruins will be in full pads for the first time Friday. They will also practice as one team, having been a split squad the first four practices. That means fewer reps for many.

“I just a made a point to the team that young players, a lot of them learn vicariously,” Neuheisel said. “Then they asked what that meant and I said, ‘You got to watch what the other guy does and make sure that you are not making the same amount of mistakes because you’re not going to get the necessary reps.’ ”

UCLA will hold a short scrimmage during the afternoon practice session Saturday.

Quick kicks

Defensive end Datone Jones will undergo surgery Friday and said he would be out “six to eight weeks.” … Tailback Johnathan Franklin had two long touchdown runs during 11-on-11 drills Thursday.

chris.foster@latimes.com

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