I think Jennings (Rashad assuming) is the most likely to get a full workload, but he has a really rough matchup, whereas Sproles has a much better matchup but is less sure to get a full workload.

I think I'd ultimately go with Jennings, just because I think he'll touch the ball at least 15 times and Sproles is unlikely to repeat last week. I don't trust Rainey in that situation.