Mankins had been mulling retirement for a few months now, and appeared to be seriously considering walking away from the NFL, so this doesn’t come as a complete surprise.
Mankins, 32, is a former first-round pick of the Patriots back in 2005. He spent nine years in New England before he was traded to the Buccaneers in 2014.
He had two years remaining on his six-year, $51 million contract that includes $30 million guaranteed. He was set to make a base salary of $6.75 million for the 2016 season.
In 2015, Mankins appeared in 15 games and was rated by Pro Football Focus as the No. 17 guard out of 82 qualifying players.
Mankins finishes his career as a seven-time Pro Bowl selection and a first-team All-Pro in 2010.