The Bills have listed offensive tackle Spencer Brown as doubtful for Sunday's game against Miami.
Brown (back) missed all three days of practice this week.
A rookie and third-round pick from Northern Iowa, Brown started the last three games at right tackle for the Bills.
In other injury news, defensive tackle Justin Zimmer is questionable with a foot injury. He practiced in full on Friday after being limited on Wednesday and Thursday.
It was previously announced that tight end Dawson Knox is out with a hand injury.
