Bell was taken to the locker room for further evaluation. His return is doubtful, the team announced. Bell hurt his left knee against the Bengals last season.
Bell was injured when he was knee-bent awkwardly while being tackled. He has rushed for 45 yards on 10 carries and caught two passes for 13 yards.
After missing the first two games of the season while serving a suspension for violating the NFL's drug policy, Bell has rushed for 556 yards and three touchdowns on 113 carries in six games while also catching 24 passes for 136 yards.