The Cubs placed Mark Prior on the 15-day disabled list Saturday with shoulder tendinitis, a move that could mean an end to the right-hander's season. Prior has been on the DL eight times in his four-year career in the majors, including three this season. The latest trip comes after he allowed five earned runs in three innings in an 8-6 loss to Milwaukee on Thursday. Prior didn't feel anything wrong with the shoulder, but a loss in velocity in the third inning led the team to send him back to Chicago for an MRI on Friday, which showed rotator cuff tendinitis.