Runningback Fantasy football Question week 4?

I need to select a second runningback for week 4 and i must say I am not very strong in that category. I have Clinton Portis but as my second I can not decide between Darren McFadden, Felix Jones, and Jamal Lewis. The only thing that makes me question the starters are the opponents and the fact McFadden is injured if he was not i'd definitely go with him. Lewis hasnt done anything but is against Cinci and Felix Jones has scored once every game and is against Washington. McFadden is against San Diego but has turf toe and seems to bother him. Help.