Bills RB LeSean McCoy sustains hamstring injury

Sep 13, 2015; Orchard Park, NY, USA; Buffalo Bills running back LeSean McCoy (25) runs the ball during the second half against the Indianapolis Colts at Ralph Wilson Stadium. Bills beat the Colts 27 to 14. Mandatory Credit: Timothy T. Ludwig-USA TODAY Sports
Sep 13, 2015; Orchard Park, NY, USA; Buffalo Bills running back LeSean McCoy (25) runs the ball during the second half against the Indianapolis Colts at Ralph Wilson Stadium. Bills beat the Colts 27 to 14. Mandatory Credit: Timothy T. Ludwig-USA TODAY Sports

The Buffalo Bills are feeling very good about themselves heading into a Week 2 showdown against the New England Patriots, but suddenly a wrench has been thrown into the machine. Running back LeSean McCoy, who the Bills acquired this offseason in a deal for Kiko Alonso, left practice on Thursday with a hamstring injury, according to ESPN.

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McCoy was finally taken off the injury report after he missed almost all of training camp with a nasty hamstring pull sustained in practice. He was able to play in Week 1 against the Indianapolis Colts but was not much of a factor, only gaining 41 yards on 17 carries to average 2.4 yards per carry. Head coach Rex Ryan says he is hoping McCoy can play on Sunday, although he was not giving any guarantees. Ryan also stated that should McCoy be on the shelf, Buffalo has no time to wallow in pity.

"“I don’t even want to think that way, but yeah, it would be definitely [next man up],” Ryan said. “But like I said, I’m not giving up on McCoy playing.”"

Buffalo seemed absolutely loaded at the running back position headed into the preseason, but things have dried up considerably. McCoy has been hurt for the most of the time he’s been near the field, and general manager Doug Whaley made the controversial decision to release Fred Jackson during the first wave of cuts in late August. Buffalo is now looking at a depth chart of McCoy, rookie Karlos Williams and a bunch of mediocrity.

Last week, Williams led the team in rushing with 55 yards and a touchdown on only six carries. Luckily for Buffalo, quarterback Tyrod Taylor is also a threat to take off and gain positive yards. Against the Colts, Taylor amassed 41 rushing yards on nine jaunts.