San Francisco 49ers running back Reggie Bush was injured in the first quarter against the Minnesota Vikings at Levi's Stadium.

He was carted off the field with a left leg injury and is questionable to return to the game.

Bush was an offseason free agency acquisition and was backing up starter Carlos Hyde. His departure from the game makes Jarryd Hayne the backup.

The Vikings recovered a Hayne fumble on his first NFL career punt return. Hyde and Hayne are the only other running backs in uniform tonight.

Update: