Petty said he felt "great" Tuesday, a day after an MRI revealed the issue.
The reigning Big 12 offensive player of the year took a shot to the back on his first series of the season in a 45-0 win over SMU on Sunday night. Petty played only the first half, and was clearly in discomfort while throwing for 161 yards with two touchdowns. He also ran for a score that put Baylor up 31-0.
Bears coach Art Briles said Petty won't play if he's not 100 percent. When asked about that, Petty smiled and said he'd be 100 percent.