Months later, and one of the Trojan quarterbacks hasn't quite given up competing.
After working out with the receivers for the third time last Friday, Mustain said he's not ready to concede to Sanchez.
"He's done a good job," Mustain said, "but I'm not done competing for anything."
While Mustain is still working for a spot on the field come fall, he applauded the work Sanchez has done leading the team since the announcement.
"He knows the system better than any of us," Mustain said. I'm just trying to catch up, keep on working and do whatever I can to be ready this season."
Mustain, who arrived from Arkansas last summer, said the team is off to a better start this summer, largely thanks to some new workout techniques.
"I think we started out a little quicker this summer, honestly," Mustain said. "We had a really good winter, did really well in spring ball and came out here without missing a beat. After a couple weeks off, we're still looking sharp."
"We've changed it up some with the stuff we've been doing, and we've done a good job with it. We're throwing really well. I hope we can keep up this pace."
Mustain said the new workout routine has helped keep spirits high while the Trojans are battling.
"I think it's been good for us. There's some new energy," he said. "I think he's trying to get us to compete even more. A lot of our stuff is set up with us going against each other, instead of just doing a drill by ourselves."
Working under strength and conditioning coach Chris Carlisle and his staff, Mustain and the rest of the team are embracing the changes on the practice field in the offseason.
"We've change up some of our workouts, and I think it's going to make us a lot better," Mustain said. "For the past year, a lot of what we were doing was the same. We've really changed it up since the spring."
Mustain and the rest of Trojan offense are scheduled to begin seven-on-seven workouts later this week.
Mustain said his redshirt year helped him transition from Arkansas' offense to the Trojans'.
"I feel pretty comfortable with the system, but I'd like to always get a lot better with it," Mustain said. "I'm just trying to cram as much in and see what happens."
Working with a vastly improved, more experience group of receivers certainly has helped Mustain throw, as he looked crisp during last Friday's offensive workout.
"I think the receivers got a lot better this offseason, especially in the spring, when I thought they looked great," he said. "I think their improvement has really helped us a lot.
We haven't had to worry so much about them. They were young, like a lot of the team, and had stuff to learn."
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