The news went from good to bad in a matter of about an hour for Detroit Lions running back
Bush, who missed a couple days of practice this week due to a calf injury, was questionable coming into the game, but was named among the 46 active players.
During warmups, however, Bush slipped in the snowy conditions and tweaked the injury.
According to 97.1 sideline reporter Tony Ortiz, Bush slammed down his helmet and was immediately surrounded by trainers. He was taken back into the locker room and did not return to the field with the rest of the team for final warm-ups before kickoff.
He came out of the tunnel with the team to start the game but hasn't played.
Bush is officially ruled as questionable to play.