The Bills, whose rushing attack is the centerpiece of their offense, lost two of their running backs Friday night in a preseason-opening 42-17 defeat at the hands of the Redskins.
Fred Jackson injured his left hand on Buffalo's second play from scrimmage, a seven-yard run, and coach Chan Gailey said Jackson would miss the rest of the preseason games.
"We hope to get him back (for the start of the regular season)," Gailey said.
Marshawn Lynch, who's likely to be the team's No. 3 back, hurt his ankle six plays later on a 20-yard run that was nullified by a penalty.
"Don't know the extent of it," Gailey said, "but we're hoping it's a lot more short-term than it is long-term."
Rookie RB C.J. Spiller, the Bills' first-round draft choice and a potential challenger to Jackson for the starting job, had four carries for 16 yards just one week after arriving at camp to sign his contract.
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