Chan Gailey did an inexplicable (literally!) job of not using C.J. Spiller against the Rams on Sunday. He won't have that option going forward, as Fred Jackson will miss the remainder of the season with a Grade 2 MCL sprain, CBS Sports NFL Insider Jason LaCanfora reports.

Jackson suffered the injury on Sunday and is expected to miss about a month, which will put him out for the remainder of the season. (We're assuming the Bills, at 5-8, aren't making the playoffs.)

"It’s not good," Gailey said on Monday morning during his weekly radio appearance on WGR 550. "It’s a minimum of two to three weeks. That’s what I was told. Something could change this morning and it could be a better prognosis, but I was told it looks like it’ll be a two- or three-week deal."

The Bills are likely to announce the full extent of the injury on Monday afternoon after Jackson gets fully tested. He missed two weeks earlier in the year with a similar injury. When he was gone, Spiller exploded.

It's possible Spiller could see a similar strong stretch late, too, as Gailey claims the Bills will lean heavily on the former first-round pick down the stretch, only using Tashard Choice to spell Spiller.

"No, we'll play C.J. as much as he can play and Tashard will rest him when he needs rest," Gailey said.

We'll see how that goes; Gailey has said before he'll use Spiller and bailed on those claims pretty quickly.

And it's possible we're seeing the end of his run in Buffalo; after spending a ton of cash on free agents this offseason, the Bills have struggled mightily. They're unlikely to make the playoffs regardless, but perhaps a strong showing down the stretch -- especially one with Spiller as a feature back -- could help mitigate the damage of sitting at home this offseason.

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