By Mary Cunningham

Will Buffalo Bills’ big-mouth Shady McCoy’s hammy heal quickly enough for the ex-Eagle to play in their opener Sept 13 against the Colts?

Bills coach Rex Ryan told reporters Thursday he is “cautiously optimistic” that running back McCoy can return in time.

Uh-oh!

The last time Rex Ryan was “cautiously” optimistic was never since he exaggerates as much as McCoy.

McCoy suffered a hamstring injury in a joint practice Tuesday with the Cleveland Browns. Ryan did not reveal the results of an MRI on McCoy’s hamstring, but had said after Tuesday’s practice that McCoy’s hamstring was intact and that no separation from the bone occurred.

The Bills were without their top five running backs for Thursday night’s11-10 preseason win over the Browns. Veterans Fred Jackson and Bryce Brown are both out with hamstring injuries, Boobie Dixon has a calf injury and rookie Karlos Williamsunderwent a medical procedure this week.

Jackson, Brown and Dixon could all return as soon as next week; Williams is out at least two weeks.