'At this point, the top five running backs on the Bills' depth chart are all on the injury report, and four of them are dealing with muscle injuries. Ryan is hoping to get Fred Jackson, Bryce Brown and Boobie Dixon back for the team's Week 3 preseason game against the Steelers, but that's no guarantee. Rookie Karlos Williams is out at least a couple weeks after a medical procedure, and now McCoy looks like he will miss a few weeks.'