The Detroit News' Justin Rogers first reported the swap.
A fourth-round pick in 2017, Roberts owned the size and red-zone production in college to project as a potential TD weapon. That potential never materialized in Detroit.
"Good competition in the (TE) room right now, so we had an opportunity to move on from Mike and hopefully get something in the future for it," Lions coach Matt Patricia said when asked about the team's decision to deal Roberts.
Injuries hindered the 6-foot-6, 265-pound tight end from ever actualizing his talent. In two seasons with the Lions, Roberts compiled just 13 receptions for 146 yards and three touchdowns. The TE showed promise last offseason, but injury derailed that progress, and he ended up playing just eight games in 2018.
Roberts was reportedly running as the fourth TE during Lions' offseason workouts, and given the compensation was probably a long-shot to make the roster out of training camp.
The 25-year-old now joins a Patriots roster trying to piecemeal production to replace Rob Gronkowski. New England's TE room includes Benjamin Watson (suspended four games), Matt LaCosse, Stephen Anderson, Ryan Izzo, Andrew Beck, and Roberts. After releasing Austin Seferian-Jenkins due to personal reasons, it's clear the Pats are throwing everything at the wall to see what sticks in an effort help replace one of the greatest mismatch advantages in NFL history.
Roberts has struggled as a blocker -- though did show slight improvements before injury struck last season -- and didn't produce as a pass-catcher in limited time. His injuries and lack of development were one reason Detroit completely overhauled the TE room this offseason. He now heads to New England where he should get more opportunities to show growth, at least until Watson returns.