Broncos running back Willis McGahee hurt his right knee early in the second quarter when he was tackled by San Diego defensive back Quentin Jammer on Sunday.
McGahee's return is questionable. He has 55 yards on seven carries, along with one catch for 18 yards.
The 10-year veteran was helped off the field and onto the bench after the hard tackle from Jammer, who was shaken up on the play as well.
The Broncos also lost special teams stalwart Omar Bolden to a concussion late in the first quarter.