The Bills placed Kolb on injured reserve, according to the NFL's official transaction wire. The team also ended return man Brad Smith's season by putting him on IR.
It's telling that the Bills were not willing to wait and see if Kolb's post-concussion symptoms quickly improved. He struggled to overcome a serious concussion in Arizona last year and has a history of head injuries.
The Bills currently are planning to start undrafted rookie Jeff Tuel in Week 1, although first-round draft pick EJ Manuel will get the call if he can recover in time. The team also released Matt Leinart on Friday, and it's possible that Thaddeus Lewis will remain on the roster as a No. 3 quarterback.
After Kolb was hurt, reports immediately surfaced questioning if the injury could be career-ending. Kolb is at the stage of his career where he's probably only going to get opportunities to be a backup quarterback, and this latest injury might even make that tough. Considering the money he's made in his career, Kolb might choose to value his long-term health over chasing his NFL dreams again.