Flowers' deal is worth a maximum value of $2.5 million, with just $50,000 guaranteed, sources tell ESPN. The Patriots placed Flowers on the active/physically unable to perform list in training camp since he hasn't been cleared to practice.
"We'll see how that goes. He hasn't played in a while, got injured in September of last year. So we'll see," coach Bill Belichick said on Wednesday.
Flowers, a two-time Super Bowl champion in New England who was selected by the team in the fourth round of the 2015 draft, spent his first four seasons with the Patriots before signing a five-year, $90 million deal with the Detroit Lions in 2019.
He appeared in four games with the Miami Dolphins last season, landing on injured reserve due to his foot.
The 6-foot-2, 265-pound Flowers isn't projected as a lock to make the roster, but he provides veteran depth behind Deatrich Wise Jr. and second-round pick Keion White in the team's multiple defensive scheme.
The team had an open roster spot and thus didn't have to release a player to make room for Flowers, who had visited the team earlier in the offseason and worked out for club officials on Monday.
Flowers, who turns 30 next week, had 21 sacks in his first four seasons with the Patriots. He also had 5.5 sacks in nine postseason games for the Patriots.
After missing his rookie season in 2015 due to injury, Flowers has 31.5 sacks, 265 tackles and 10 forced fumbles with 4 recoveries over his career.