Ryan says Williams wore a neck brace and is still feeling stiff and sore after being examined and released from the hospital on Sunday.
Though tests revealed the injury wasn't serious, Ryan says it's ''probably a stretch'' to expect Williams to play in Buffalo's game at Miami on Sunday.
Williams was hurt while diving headfirst in an attempt to tackle Patriots receiver Julian Edelman in the third quarter of a 40-32 loss to New England. Williams was placed on a stretcher and his body immobilized before being loaded into an ambulance.
He was released from a hospital about three hours later.
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