Jets linebacker C.J. Mosley (57) during an NFL football game...

Jets linebacker C.J. Mosley (57) during an NFL football game against the Tennessee Titans, Sept. 15, 2024, in Nashville, Tenn. Credit: AP/John Amis

In some ways, the Jets’ biggest problem this season is the same as it was last season. They lost their quarterback early and nothing was ever quite the same.

The difference is that last year it was Aaron Rodgers whose injury scuttled the schedule and hampered a promising offense. This time around it was C.J. Mosley and his absence as “quarterback of the defense” that swiftened the team’s demise and brought them to this point, playing out the string with five meaningless games to go.

It’s not as glaring because Jamien Sherwood has stepped in for Mosley and played much better than Zach Wilson and the rest of the ragtag passers did last year filling in for Rodgers. Sherwood, a converted safety, has recorded a team-high 103 tackles in his first extended stint as a starter.

But while Sherwood’s own production has been fine, the intangible ripples that emanate from that position have been impacted greatly. Sherwood, through no fault of his own, simply lacks the NFL wisdom and instincts that Mosley added each time he stepped on the field.

“Missing C.J., you are missing one of the best players in the NFL,” defensive lineman Solomon Thomas told Newsday on Thursday. “You are missing one of the best leaders in the NFL. C.J. is a role model for us all ... His attention to detail is out of this world. You miss his leadership, you miss his voice, you miss his instincts, the way he plays the game. He is one of the best for a reason. He’s irreplaceable.”

He was the air traffic controller choreographing all the rest of the Jets buzzing around his tower. Now their formations just aren’t as precise — maybe not to the point of mid-air collisions but noticeable to those who live by such details.

“He’s so unique in his ability to lead and elevate those around him,” interim coach Jeff Ulbrich said last week. “He brings not just leadership but this confidence and poise and toughness that it’s hard to replicate ...

“There’s been times where he got us into calls that weren’t part of the check system, and just a call where he thought it was best in that moment, which is, in my experience, it’s been one of the only times I’ve ever seen that done, so he’s just so unique and special in that way.”

It isn’t just the Jets who appreciated that. None other than Bill Belichick has spoken glowingly of Mosley’s ability to put the whole defense in the right place to stop plays.

“I think Mosley is the guy who is really a key guy for them on the defense,” Belichick said before his Patriots’ game against the Jets in September 2023. “He’s one of the best, most instinctive players in the league. Always a problem ... One of the best in the league, for sure.”

The biggest statistical change between the past two years, when the Jets played what most considered to be championship-level (or at least championship contender-level) defense, is in their inability to come up with stops in critical situations. Remarkably, this three-win squad is ranked third overall in yardage allowed this season (301.2) and is middle-of-the-pack 15th in points allowed (22.3). The defense has given up game-winning drives in the fourth quarter to the Seahawks, Colts, Patriots and Broncos, though. That’s four of the nine losses in a season in which they could not slam the door shut.

Mosley hasn’t been on the field for any of those. After playing more than 1,000 defensive snaps in each of the previous two seasons, he’s logged barely over 100 this year. He played 63 snaps in the opener against the 49ers and 16 in Week 2 against the Titans, when he first hurt a toe and missed several weeks. He came back and played nine against the Bills in Week 6 and 22 against the Steelers in Week 7 but hasn’t played since as he fights through a neck injury.

And just like last year’s maimed quarterback, he is spending December trying to get back on the field. Mosley has been testing his neck for the past few weeks and even playing some scout team defense to try to return to action. “You don’t see that out of future Hall of Famers,” Thomas said.

Mosley also is involved in team meetings and drops in and out of other position groups during the week to check in on them and try to make sure everyone is in the right place from a schematic and morale standpoint.

He was a full participant in Wednesday’s practice but did not practice Thursday. He almost certainly won’t play on Sunday in Miami, there is a pretty good chance he won’t play again this season, and, at age 32, the lingering possibility that he will never play again.

“Jamien has done an amazing job,” Thomas said. “He’s been a great professional, a great teammate, a great leader. How he’s stepped into that position has been awesome and I’ve been so proud of his growth and it’s been so cool to see him evolve.”

But he’s no Mosley. That’s not a slight. It’s just a fact. Just as no one on the team last year could be Rodgers in his stead. Maybe Sherwood can grow into the kind of player Mosley has been for much of the past decade. He’s not there yet, though.

“There definitely is a similarity,” Thomas said of the Missing Quarterback Theory for this defense’s woes that mirrors what happened to the offense last year. “[Mosley] is the heart of our defense, the voice of our defense. He’s a guy who gets us rolling. We’re definitely missing him and the impact he brings.”

Would the Jets have been better this year if Mosley had remained healthy and played all season? Probably. But as with Rodgers’ absence last year, it’s a haunting hypothetical. We’ll just never know. All we can know is what happened without them. And in neither case was it pretty.