Bills defensive tackle Marcell Dareus missed practice all week with a hamstring injury and is doubtful for Sunday's game against the 49ers, coach Rex Ryan said Friday.
None of the Bills players have been declared out yet for the game, though nine players are questionable:
-- Left tackle Cordy Glenn (ankle)
-- Linebacker Zach Brown (ankle)
-- Cornerback Corey White (shoulder)
-- Defensive tackle Corbin Bryant (ankle)
-- Punter Colton Schmidt (right quad)
-- Center Patrick Lewis (knee)
-- Safety Aaron Williams (ankle)
-- Tight end Charles Clay (knee)
-- Tackle Cyrus Kouandjio (ankle)
Ryan said Dareus will likely test his hamstring during warmups Sunday.
"I'm not one of these coaches that, 'Well, you gotta practice,' or something like that – if you're a great player. Then I'll throw you in there," Ryan said. "We'll see how he's feeling."
Ryan said linebacker Zach Brown – the NFL's leader in tackles – should be good to play, as should punter Colton Schmidt. However, Cyrus Kouandjio will probably be held out.
"I think in a pinch, we probably could go with him," Ryan said of Kouandjio. "I'm not so sure he will be active this game, probably not. But he seems to think that he could go."
Ryan also said he's seen good progress from Seantrel Henderson, who isn't on the injury report but was just added to roster this week after coming off suspension.
"He seems to be doing pretty well for us. I'm excited about him just getting out there and really getting a full week of work in. So we'll see what that means moving forward."
Ryan also said Friday that safety Colt Anderson, who was placed on injured reserve earlier this week, has a broken arm.
49ers injury report
Out: Cornerback Jimmie Ward (quad).
Questionable: Linebacker Ahmad Brooks (groin), defensive tackle DeForest Buckner (foot), defensive tackle Glenn Dorsey (knee) and safety Jaquiski Tartt (quad).
Story topics: Marcell Dareus