ST. LOUIS -- St. Louis Rams running back Steven Jackson sat out most of the final three quarters of Sunday's victory over the Washington Redskins with a groin strain that worsened on his last few carries.
Jackson didn't play after drawing an unsportsmanlike conduct penalty for spiking the ball in protest after he was ruled short of the goal line on a third down carry from the 1.
Coach Jeff Fisher said Jackson was held out because of the injury, not because he was being disciplined.
The Rams went with rookie Daryl Richardson while Jackson stood on the sideline, helmet in hand. During the game, a team spokesman said Jackson was fine.
One play before the penalty, referees ruled that Jackson lost a fumble at the 1. The call was reversed when the Rams challenged.
Jackson had 58 yards on nine carries. He's the Rams' career rushing leader and entered the year with seven consecutive 1,000-yard seasons.