Fred Jackson had a wonderful first 10 weeks of the season last year before it all ended with a broken right leg. In the first game this season, Jackson has been sidelined again.
The running back went out in the first half and CBSSports.com's NFL Insider Jason La Canfora reports that Jackson suffered a sprained LCL.
La Canfora writes that Jackson will undergo an MRI on Monday.
Before leaving the game, Jackson had 15 yards on six carries in what was a terribly disappointing game for Buffalo.
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