Buffalo Biils quarterback Kevin Kolb left Saturday’s preseason game with a concussion. Tim Graham of the Buffalo News reports that the Bills are concerned Kolb’s concussion may be career-ending, and they’re proceeding with that in mind. The concussion suffered on Saturday was at least the third documented concussion of Kolb’s career, and who knows how many actual concussions Kolb might have suffered that were undocumented.

The Bills are now approaching the injury as if they have a real need for quarterback help. Their other quarterback E.J. Manuel had knee surgery recently and is out indefinitely. The Bills signed Matt Leinart and traded for Thaddeus Lewis yesterday in response to the injury. NFL teams have to reduce their rosters to 75 players by tomorrow.

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[via Pro Football Talk]