The Jets sustained a hit to their offensive line depth on Tuesday.

Veteran guard Kelechi Osemele is undergoing season-ending shoulder surgery, a source confirmed.

Osemele, 30, was one of the Jets’ big acquisitions this offseason. They traded a fifth-round draft pick to the Raiders for Osemele and a sixth-round pick in March, hoping he could solidify the offensive line. Osemele was their biggest change to the offensive line until August, when they signed Ryan Kalil.

The trade flopped, though. Osemele failed to regain the form he showed when he made two Pro Bowls. He struggled mightily in the first three games and the coaches were considering benching him before he injured his shoulder in a padded practice before the Eagles game.

The Jets have been thrilled with the play of Alex Lewis, who replaced Osemele. It seemed unlikely that Osemele would regain the starting job even if he did get healthy.

The trade, made by former general manager Mike Maccagnan, looked like a good idea in March. But Osemele was a big part of the offensive line’s struggles against the Browns and Patriots in Weeks 2 and 3. He is signed for 2020, but the Jets are not expected to bring him back. He is due to make $11.4 million next year. None of that is guaranteed, so the Jets can cut him in the offseason and move on.

Osemele played three seasons for the Raiders, making two Pro Bowls, after four seasons with the Ravens.

The Jets signed safety Blake Countess on Tuesday. He played the past three seasons for the Rams and was in training camp with the Eagles this year. The Jets cut cornerback Arthur Maulet to open the roster spot. The Jets also signed defensive lineman Corbin Kaufusi to the practice squad after the Ravens signed defensive back Bennett Jackson off of their practice squad. Kaufusi joins his brother Bronson, who is also on the Jets’ practice squad.