Buffalo Bills running back Fred Jackson is expected to miss 3 to 4 weeks after injuring his right knee during Sunday's 48-28 loss to the New York Jets, NFL.com and NFL Network's Albert Breer reported Monday, citing a source who has spoken with the player.
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Jackson underwent an MRI on Monday, but it's uncertain if his lateral collateral ligament is torn or sprained, Breer reported. Jackson has experienced significant swelling and is being advised to rest for seven to 10 days before undergoing additional testing. Surgery will not be required, according to the source.
This setback comes on the heels of Breer reporting that Bills wide receiver David Nelson has been lost for the season with a torn anterior cruciate ligament.
Jackson signed a two-year contract extension with Buffalo during the offseason, following a spectacular 2011 campaign that was cut short when he suffered a fractured right fibula in November.
Bills coach Chan Gailey spoke all summer of using a rotation of Jackson and C.J. Spiller this season. One week in, those plans have been altered. Spiller now assumes the workhorse role, and his 169-yard outburst against the Jets on Sunday was the silver lining in an otherwise disastrous opener.
Follow Marc Sessler on Twitter @MarcSesslerNFL.