Bills center Eric Wood, arguably the team's best offensive lineman, tore his ACL on Sunday and will miss the rest of the season, according to a league source.
Wood left in the third quarter of Buffalo's 44-7 loss to the Cowboys.
"He means a lot to us," quarterback Ryan Fitzpatrick said. "We'll see. I have no idea how he's doing or what it is. Eric Wood obviously means a lot to our guys up front."
Sunday's loss dropped the Bills to 5-4, their second straight lopsided defeat.
Buffalo's Eric Wood Has Torn ACL