The worst-case scenario for Jackson, according to NFL analyst Ian Rapoport, is that he'll miss four weeks with the injury, as it wasn't bad enough to require surgery.
Not all injury news is bad for #Bills: worst-case for RB Fred Jackson (groin) is to miss 4 weeks, I’m told. He has his eyes on 11/6 vs KC— Ian Rapoport (@RapSheet) October 20, 2014
Jackson has already been ruled out of action for Week 8, according to Jason La Canfora of CBS Sports, leaving the Bills thin in the backfield for a Week 8 road trip to play the New York Jets. C.J. Spiller and Jackson have split the carries in the backfield for Buffalo in 2014, but the team will be without both, as Spiller is done for the season with a broken collarbone, according to Pro Football Talk.
Without the team's pair of top running backs, the Bills will instead have to rely on the contributions of Boobie Dixon and Bryce Brown until the return of Jackson.