Updated 7:25 p.m. ET
The Patriots signed DT Gerard Warren and released DL Landon Cohen on Tuesday, a bit of a shakeup on their defensive line.
Cohen was signed by the team on Sept. 21 and played as a reserve in the team's Week Three loss to the Bills. He was signed as insurance in case DT Albert Haynesworth was unable to play. The team has already lost DLs Myron Pryor and Mike Wright for the season.
Warren played for the Patriots last season, starting 10 games. He recorded 28 tackles, but was released in September just before the regular season began.