Swift (concussion) wasn't in attendance for the open portion of Thursday's practice, Kyle Meinke of MLive.com reports.
Swift was listed as a limited participant Wednesday for the Lions' first practice of Week 13, but his absence from the team facility a day later may hint at a possible setback in his recovery from the concussion he sustained in a Week 10 game against Washington. Prior to Thursday's practice, interim head coach Darrell Bevell didn't provide much information behind why Swift was missing, but at this stage, the running back is looking unlikely to clear the NFL's five-step concussion protocol ahead of Sunday's game in Chicago. If Swift is in fact sidelined for a third straight game, Adrian Peterson and Kerryon Johnson would handle the bulk of the snaps and touches out of the Detroit backfield.