Walker was just five of eight for 33 yards passing in Saturday's preseason loss at Dallas.
Walker moved up to No. 3 on the QB depth chart before last week's preseason game, but may fall back to the No. 4 spot after he didn't do much and Stephen Morris played well. With Scott Tolzien struggling in the preseason and Andrew Luck still out with a shoulder injury, it's possible any of the Indianapolis quarterbacks could figure into the mix early in the regular season.