Conner left the game after rushing for 60 yards and two touchdowns on 15 carries.
James Conner suffered a lower leg contusion in the Steelers' 33–30 loss to the Chargers, coach Mike Tomlin told reporters on Sunday.
The Steelers running back did not return to the game after suffering a lower leg injury late in the fourth quarter of Sunday's matchup.
Conner, who had 60 yards and two touchdowns on 15 carries, left the field in obvious pain. Conner was helped off the field by the team's doctors and head trainer, and was evaluated on the sideline before he was seen limping to the locker room.
Rookie running back Jaylen Samuels took Conner's place in the lineup and scored on a 10-yard touchdown pass from Ben Roethlisberger shortly after Conner exited the game.
The Steelers fell to 7–4–1 on the season and will travel to Oakland on Sunday for a Week 14 matchup against the Raiders.