San Francisco 49ers RB Reggie Bush was seen on crutches in the locker room following the team's 27-6 loss to the Rams in St. Louis.

FOX Sports' Mike Garafolo is reporting that the 49ers are fearing the worst. They believe that he may have a torn ACL. He will have an MRI to confirm the injury, which may end his season.

Bush slipped on the sideline concrete at the Edward Jones Dome while running out of bounds on a punt return. He did not get back up and was eventually carted to the locker room.

RB Mike Davis (hand) also left the game. With RB Carlos Hyde (foot) inactive, that left only RB Kendall Gaskins to play in the game. Gaskins was promoted from the practice squad on Saturday. To make room for him, the team released RB Jarryd Hayne, the former Australian rugby league star. It was a move that many fans questioned.

It is highly likely that the team will now re-sign Hayne to the active roster if he clears waivers on Monday.