Running back Tim Hightower tore the ACL in his left knee and will miss the rest of the season, becoming the third Redskin to suffer such a fate this season.
"He was playing well," coach Mike Shanahan said. "It's always tough to lose a player like that, who leads both on and off the field."
Meanwhile, Shanahan said receiver Santana Moss will miss five to seven weeks after undergoing surgery to repair broken bones in his left hand. Moss needed three pins inserted in the area of his index finger.
Two weeks ago, the Redskins lost guard Kory Lichtensteiger for the season with an ACL tear. Left tackle Trent Williams suffered a high ankle sprain and tight end Chris Cooley broke his left index finger.
"I don't think I've ever lost this many on one side so quickly," Shanahan said.
Hightower rushed for 321 yards in the five games he played this season. He gained 88 yards on 17 carries Sunday before getting hurt. He also caught 10 passes for 78 more yards this season and was their best pass protector among the running backs. Ryan Torain and Roy Helu will replace him.
He did not say who would replace Hightower on the roster, once he's placed on injured reserve. Rookie running back Evan Royster is on the practice squad.
Linebacker London Fletcher injured his hamstring, but Shanahan said, "I don't think it's that serious."
This summer, defensive end Jarvis Jenkins also tore his ACL and was placed on injured reserve.
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