Manziel's shoulder on his throwing arm was slammed into the ground after a scramble in the red zone, as CBS illustrated:
Johnny Manziel lands on his right shoulder, begins to walk off field, then stops for medical treatment.— Eye on College FBall (@EyeOnCFB) October 19, 2013
Manziel returned to the game in the fourth quarter with Texas A&M down 38-34. The Aggies went on to lose the game 41-45.
Manziel played the following week against Vanderbilt, leading the Aggies to a 56-24 win.