Tom Curran from Comcast Sportsnet NE tweeted that Mankins did not travel with the team to Buffalo and that he is out on Sunday.
Mankins missed all three days of practice this week and was listed as
questionable on the injury report. Mankins managed to play fifteen games
in 2011 on a torn-ACL.
Expect Donald Thomas to take over the left guard role.
The Patriots announced on Saturday the team has re-signed offensive lineman Matt Tennant, bringing their roster back up to 53 after releasing Kellen Winslow on Thursday.
Tennant's previous tenure with the Patriots lasted just three days. He was signed on Sept. 1 and released on Sept. 4.
Chances are this is a stop-gap move just for this weekend. If New
England thought they would be needing a guard or center for the
long-haul, they likely would have brought Thomas Austin or Jeremiah Warren
off the practice squad. Signing Tennant means that the Patriots
wouldn't need to risk losing Austin or Warren through waivers once they
no longer needed an extra offensive lineman on the 53-man roster.