Avery Williamson has suffered a torn ACL and will miss the entire 2019 season.
The injury happened on a fluke play late in the second quarter, when Williamson was the only defensive starter in the game.
Williamson started every game last season, missing only five defensive snaps. The Jets figured to have a strong inside-linebacker tandem with Williamson and C.J. Mosley, one of their top free-agent additions.