The Jets’ defense fancies itself as one of the best in the NFL. 

Here’s the thing, though: Top defenses don’t allow 16-play, 96-yard touchdown drives that swallow 8:15 off the clock in a game the team absolutely, positively needs to win. 

Top defenses don’t allow 251 yards of offense in the first half. They don’t allow 13 first downs and 41 plays and 20:11 in time of possession in the first 30 minutes. 

The season-squashing 19-3 loss Thursday night to the Jaguars at MetLife Stadium was a sobering blow to the Jets’ defense, which was on its back foot all night thanks to some dynamic and creative play calling by Jacksonville head coach Doug Pederson, who put on an absolute clinic. 

That 96-yard drive represented a series of body blows from which the Jets never recovered. 

“Just embarrassed, really,’’ cornerback D.J. Reed said afterward. “This was embarrassing. How we played, the product we put out was just embarrassing.’’ 

Speaking more of the debilitating drive, Reed said: “I don’t know what to call it, man, it was disappointing. Not our standard of football. It was Thursday night, we had a great opportunity to show our standard of football and how we play, how we’ve been playing all year, and I felt like we didn’t do that on defense today.’’ 

Rookie cornerback Sauce Gardner sounded utterly bewildered by what happened on that drive. 

“I don’t even remember what happened,’’ Gardner said. “We shouldn’t have let them march up the field like that. It was extremely disappointing.’’ 

How dominant was the drive? 

The first third down the Jaguars faced on the drive was third-and-goal from the Jets’ 1-yard line — the 16th and final play of the possession. 

The Jaguars’ 6-foot-6 quarterback, Trevor Lawrence, dove over the goal line for a TD on the play for a 10-3 lead Jacksonville never relinquished. 

“It’s a s—ty feeling,’’ defensive tackle Sheldon Rankins told The Post. “We just can’t allow it — especially in tight games like this. You’ve got to be able to get off the field. You’ve got to be able to get stops no matter what. That is our job. 

“We set the standard that we don’t allow things like that to happen. To allow it to happen is not up to our standard. They were already backed up. You’ve got to be able to win that field-position battle and get the ball back in your offense’s hands and give them the opportunity.’’ 

On that long drive, the Jaguars bled out the Jets’ defense with a series of paper cuts. 

Eventually, the defense was going to break, and it did with the Lawrence TD for the 10-3 Jacksonville lead. 

The Jets’ defense had no answer for anything the Jaguars threw at it, beginning with running back Travis Etienne, who ran 17 times for 64 yards in the first half. 

Lawrence constantly hurt the Jets with his running ability, rushing for 41 yards and the TD on five carries in the first half as the Jaguars detonated the Jets’ playoff dreams. Gang Green’s defense played as if it had no idea Lawrence was a threat to run with the ball. 

Jaguars tight end Evan Engram, the former Giant who never reached his potential in blue at this very stadium after he was drafted in the first round, played as if he thought his old team was on the other side of the field and he wanted to prove a point. 

Engram looked uncoverable, catching six passes for 106 yards. 

The Jets’ offense, which was anemic all night, gave the defense no help. 

But what made Thursday so alarming is that this, the fourth consecutive loss for the Jets (7-8) and their fifth in the past six games, was another in a string of defensive failures. 

Four days earlier, the Jets’ defense failed to hold a 17-13 lead late in the game, allowing the Lions to march down the MetLife turf and score the game-winning TD with 1:49 remaining.