Todd Bowles’ defense may have just been dealt a major blow.

Veteran inside linebacker David Harris — the quarterback of the unit — did not return after injuring his shoulder late in the first half.

Coach Todd Bowles said after the game that he wasn’t sure of the severity of the injury, but he added that Harris would undergo tests on Sunday.

The 10-year veteran was not on the sideline at all during the second half and he wasn’t spotted in the locker room after the game.

Harris, 32, hasn’t missed a start since 2008.

Offense stalls without its star

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In the aftermath of a subpar performance, Ryan Fitzpatrick acknowledged that “it’s tough” to gauge where the first-team offense is when Brandon Marshall isn’t on the field.

The star wide receiver was a surprise scratch Saturday night against the Giants because of a sore hip, according to Bowles. Had it been a regular-season game, Marshall would have played, the coach said.

But while rookie receivers Robby Anderson and Jalin Marshall made impressive plays in Marshall’s place, the veteran’s absence was a huge void for the first-team offense.

“I think we feel pretty good right now [as a unit],” Fitzpatrick said of the group. “I don’t know that those three games were a great indication of where we feel we are. We obviously have got a tough defense in Cincinnati that we’re going to open up with and we can’t start slow. We’ve got to come out firing.”

Ex-Chaminade star Catapano starts

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Long Island native Mike Catapano had two tackles, including one for a loss in his first preseason start. The Chaminade and Princeton alum earned himself first-team reps in practice this week and got the start in place of injured rookie Jordan Jenkins (calf.) Catapano recently returned to practice after rehabbing a Lisfranc injury that curtailed his promising first season with the Jets in 2015. The injury — which he suffered in the Jets’ 23-20 win over the Giants in Week 13 — occurred shortly after he sacked Manning in the game.

More inactives

In addition to Marshall and Jenkins, WRs Quincy Enunwa, Kenbrell Thompkins, Kyle Williams, Devin Smith, CB Dexter McDougle, RBs Romar Morris and Dominique Williams, S Dion Bailey, RT Breno Giacomini and DLs Lawrence Thomas and Jake Ceresna were also inactive for the Jets.