A person familiar with Fred Jackson's injury says the Buffalo Bills running back has a sprained ligament in his right knee that could force him to miss the final three games of the season.
The person said Monday that Jackson doesn't require surgery but will miss between two and four weeks. The person spoke on the condition of anonymity because the team has not revealed the nature of the injury.
During his weekly show on Buffalo's WGR-Radio on Monday, coach Chan Gailey characterized Jackson's injury as "not good," and expected the player to miss at least two weeks.
Jackson was hurt with about 5:30 left in a 15-12 loss to St. Louis on Sunday, when he was tackled following a 2-yard run.
Buffalo (5-8) meets Seattle (8-5) at Toronto on Sunday.
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