Former Arkansas QB Mustain enrolls at USC

Mustain was on campus for summer classes but could not be reached for comment. He will redshirt next season and be eligible in 2008.

"We're excited about him," Carroll said. "I think it's a great investment in the future.

"He won a lot of games at Arkansas playing in a pretty conservative offense for a quarterback."

Mustain, who is 6 feet 3 and 205 pounds, passed for nearly 900 yards and 10 touchdowns last season for an Arkansas team that lost its opener, 50-14, against USC. The Razorbacks rebounded to finish 10-4 with running back Darren McFadden, a Heisman Trophy finalist, leading the way.

Mustain is the second Arkansas player to transfer to USC since the end of the season. Receiver Damian Williams, Mustain's former teammate at Springdale High in Arkansas, enrolled in January and is recovering from shoulder surgery. He also will be eligible in 2008.

"It's good to have him," Williams said. "I think he's feeling a little bit of everything. You're always nervous when you go into a new environment, but he'll roll with the punches and fit in just fine."

Mustain visited USC twice before choosing the Trojans over Tulsa, where former Arkansas offensive coordinator Gus Malzahn, Mustain's high school coach, is co-offensive coordinator.

With John David Booty in his final year of eligibility, Mustain is expected to push Mark Sanchez, who will be a redshirt sophomore this fall, for the starting job next spring.

"Mark is the likely one to have the edge because he's been around

gary.klein@latimes.com