‘Head coach Sean McDermott saying earlier Wednesday that Knox dealing with a hamstring injury suffered while training recently. With Knox on the mend, Zach Davidson and rookie Jackson Hawes seeing a little more run. Spencer Brown began camp on the physically unable to perform list as he’s dealing with, what McDermott called, his back flaring up. The Bills coach said Brown had back surgery just last offseason and, because of that, the team taking an extra cautious approach this time of year.’