NEW YORK (WFAN/AP) — The Jets’ up-and-down defense got some bad news Monday.

The team announced linebacker Bryan Thomas will miss the rest of the season with a torn left Achilles tendon. He suffered the injury in the team’s 34-17 loss at Baltimore on Sunday.

Thomas is in his 10th season with the Jets and their longest-tenured player, but is due to become a free agent after this season. While never a flashy player during his career, Thomas has been a key part of the defense and led Rex Ryan’s squad with six sacks last season.

The 32-year-old Thomas was hurt in the first quarter Sunday, and was on crutches and in a walking boot when he left the stadium. An MRI on Monday morning confirmed the severity of the injury.

“That’s going to be a huge loss to us, obviously,” Ryan said.

Jamaal Westerman, Josh Mauga and the newly signed Aaron Maybin, who had his first NFL sack Sunday after two unproductive years in Buffalo, are candidates to replace Thomas. But Ryan also wouldn’t rule out the team looking for help elsewhere. In fact, the Jets had former Patriots outside linebacker Tully Banta-Cain in for a workout a few weeks ago, and New York just so happens to play New England next Sunday.

“I’m not ready to anoint anyone as the starter there,” Ryan said.

Thomas had 12 tackles this season and has 31 careers sacks, seven forced fumbles and six fumble recoveries. He was the Jets’ first-round pick out of Alabama-Birmingham in 2002, and saw his career begin to thrive when he was moved from defensive end to outside linebacker four years later.

“It’s tough when you lose a guy that is a true Jet, a guy that’s played a lot of snaps for us,” safety Jim Leonhard said.

Linebacker Garrett McIntyre suffered a concussion in the game at Baltimore, and will be day to day.

Ryan and the Jets are hoping center Nick Mangold, who missed his second straight game because of a high ankle sprain, will be able to practice at least on a limited basis Wednesday. Mangold tested his right ankle out before the game and felt good – “He had no issues,” Ryan said – but wasn’t ready to play.

Who should start for Thomas? Be heard in the comments below…

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