Who to start in the flex position for the championship game?

I will go w/ I. Bruce. Ward is questionable and likely to be 2nd string rb behind Jacobs. Parker has a tough matchup at Tennessee. Dunn has only 2 TDs this year and less than 50 rushing yds in his last 2 games. Jackson can run hot and cold. I. Bruce and SF Off. Coord. M. Martz are going back to St. Louis to face a Rams defense that has only 1 interception in their last 7 games. SF Qb Hill has 230+ ping yards in 3 of his last 4 games. Bruce is my pick.