St. Louis Rams running back Steven Jackson left in the third quarter of his team’s Week 17 game against the San Francisco 49ers with an injury to his left arm. His return to the game is questionable. The Rams made an official announcement on Twitter after Jackson was taken into the locker room.

Jackson collided with 49ers safety Dashon Goldson. He went to the sidelines grimacing in pain. The Rams kicked a field goal on the drive, but San Francisco answered with a touchdown on the next possession.

Jackson left the game with 76 rushing yards on 16 carries. Cadillac Williams is his primary backup, and the Rams will likely use Jerious Norwood for a few carries in relief.

Last week, Jackson became the seventh running back in NFL with seven consecutive seasons of 1,000 rushing yards. Jackson has been the focal point of the Rams offense and a bright spot in otherwise forgettable season.