He was with the team earlier this month for a few days before being released prior to opening day.
New England had a roster spot open when it released tight end Kellen Winslow Jr. Thursday. It's curious, though, that with three healthy o-linemen on the practice squad, the Patriots chose to bring on a player with virtually no experience in their system.
Tennant was assigned jersey number 69.
UPDATE… 6:58 pm
According to CSNNE's Tom Curran, left guard Logan Mankins did not travel to Buffalo with the Patriots and will not play against the Bills. Mankins (hip) did not practice all week.