UCLA first-year coach Jim Mora has enough challenges on his plate. He’s trying to revive a once-proud program in a tough market where USC reigns while shoring up a leaky defense and starting a redshirt freshman quarterback.

Injuries? Don’t even go there. The Bruins have been relatively healthy thus far through camp, but here are a few concerns.

LB Patrick Larimore (concussions): The concern isn’t whether Larimore will play. He won’t. He retired after suffering his second concussion in a six-month span early in camp. The concern is: Do the Bruins have anyone who can fill the shoes of their 2011 leading tackler? This was not a good defensive unit last season. Losing one of the better players won’t help. Junior Todd Golper is likely to fill the middle linebacker role.

O-linemen Jeff Baca, Greg Capella and Alberto Cid (concussions): Baca had been out nearly two weeks with a concussion but returned and participated in practice on Wednesday. He and Capella are projected as starters while Cid was a part-time starter last season and is battling for a job this year. The Bruins need continuity and experience along their offensive line with redshirt freshman QB Brett Hundley taking the reins. They’re off to a shaky start.

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