The 49ers promoted practice squad running back Raheem Mostert to the 53-man roster for the final game of the regular season, the team announced Saturday afternoon.
The 49ers placed center Marcus Martin on injured reserve to make room for Mostert on the roster. Martin was ruled out for the game with an ankle injury. He becomes the 19th player the 49ers have placed on injured reserve this season, not including nose tackle Ian Williams, who was released off injured reserve in October.
Mostert is expected to take the role of Mike Davis, who appeared to foreshadow a move with a post on social media.
"Guess I gotta work even harder," Davis wrote Friday on his Twitter account.
Shaun Draughn and DuJuan Harris are the two other healthy running backs on the 49ers' roster. Carlos Hyde was placed on injured reserve this week with a knee injury.
Mostert, who spent the past four weeks on the practice squad, entered the NFL last season with the Philadelphia Eagles as an undrafted free agent. He has also spent time with Miami, Baltimore, Cleveland, the New York Jets and Chicago.
He appeared in 11 games last season with three different teams. He played two games earlier this season with the Bears. He has never carried the ball in an NFL game, but he has averaged 27.9 yards on 19 kickoff returns.
Mostert (5-foot-10, 197 pounds) rushed for 529 yards and three touchdowns on 93 rushing attempts as a senior at Purdue in 2014.