Who will be Johnny Football's backup?

Heisman Trophy winner and Texas A&M quarterback Johnny Manziel ran the football 201 times last season. Manziel ran the ball more than some of the nation's top running backs such as North Carolina's Giovanni Bernard and Kent State's Dri Archer. Concern over a potential injury has to be the back of the minds of the Aggies' coaching staff. The competition to become Manziel's backup is crucial if the unthinkable were to occur.