Kearse was carted off the field early in the first quarter of the Lions' preseason clash with the Patriots.
Lions wide receiver Jermaine Kearse suffered a broken leg and "associated injuries to his ankle" less than three minutes into Detroit's first preseason game on Thursday night, according to NFL Network's Ian Rapoport.
The 29-year-old veteran was carted off the field after a Patriots defender attempted to tackle running back Ty Johnson but landed on the back of Kearse's left leg instead. Kearse left the field in an air cast following the injury.
Kearse finished the 2018 season—his second and final with the Jets—with 37 receptions for 371 yards and one touchdown through 14 appearances. He has tallied 17 touchdowns during his seven NFL seasons.
The Lions signed Kearse to a one-year deal worth a maximum of $2.5 million this season.
The Super Bowl XLVIII champion began his NFL career with the Seahawks, who signed Kearse as an undrafted free agent in 2012.