It’s over-reaction Monday and nowhere is that truer than with the Los Angeles Chargers.

Before L.A.’s defense blew a late lead after getting pushed around for four quarters in a 36-34 loss to the Miami Dolphins, much was promised from Chargers head coach Brandon Staley.

Entering his third year with the club, he crossed his heart and promised that his sorry defense — last seen coughing up a 27-0 cushion in a playoff loss to the Jacksonville Jaguars — would finally show its teeth.

To Staley’s point, it was time to follow the money.

Those Chargers that are handsomely paid by the Bolts, and finally healthy, would lead to a renewed confidence in a unit which has been shoddy since Staley took over after earning his NFL stripes as an, uh, defensive wizard.

But the Dolphins pulled the curtain back on the Chargers, exposing a defense which was chasing all day, one that was all bark and little bite.

If quarterback Justin Herbert and the offense does its part by plopping a 34 on the scoreboard, the defense has to do more than rest.

Instead it was more of the same and that brings us back to the dollars and sense of two of the biggest contracts among the defenders after the group surrendered 538 yards.

Yes we’re looking at you, Joey Bosa and J.C. Jackson.

Bosa, an edge-rusher had one more tackle than his teammates in street clothes. That’s not much of a dividend when playing on a five-year, $135 million contract which guarantees him $102 million.

We get inflation and all, but one tackle from a guy with an average annual salary of $27 million.

Yikes!

Jackson, a cornerback, had tire marks across his back he was burned so often. But getting beat happens in the NFL, especially against the high-octane Dolphins.

Still, there’s a price for stupidity and twice the Chargers were asked to erase Jackson’s miscalculations.

We mention that because not only did a lost-in-space Jackson collect zero tackles, but it was his bonehead decision when drawing a pass-interference penalty near the end of the first half that was a head-scratcher.

We do tip our hat to Jackson on getting an end-zone interception, although he quickly pulled a Marlon McCree when failing to fall down after his pick.

Longtime Chargers watchers know of what we speak, as Jackson tried to return the interception the end zone with dreadful results.

He advanced it but four yards, which preceded a quick four-and-out with a wobbly punt. The Dolphins assumed great field position and quickly scored a touchdown.

Jackson missed most of last year with a bum knee. He started this year with the Chargers wondering if they’ll be bummed they awarded him a five-year $82.5 million pact, with $40 million guaranteed.

Staley’s take on Jackson’s four quarters of work?

“Not very good,’’ he said.

Oh boy!

We won’t mention Kahlil Mack, another pricey edge rusher. On second thought, why not?

Mack, performing on a six-year, $141 million pact, did have twice as many tackles as Bosa and that’s not saying much. With his deal including a $90 million guarantee, it’s a safe bet the Chargers were expecting more.

“I didn’t do a good enough job getting us adjusted through the game,’’ Staley said, admitting that he was hookwinked by Dolphins coach Mike McDaniel. “We tried.”

We tried?

This from an organization which promised to make a Super Bowl run by reworking numerous contracts in the offseason and signing Herbert to his massive second deal.

We tried?

Now the Chargers waltz off to Tennessee, where they’ll be asked to stop punishing running back Derrick Henry.

If the Chargers can’t fortify their defense after taking a haymaker from the Dolphins, their Super Bowl aspirations will look like a fish out of water.

“We have to move past this one, learn from all the tough things that we’re going to have to learn from in this game, and then get moving on to the Titans,’’ a glum Staley said.

The Chargers will do so by remembering the Dolphins and how they uncovered the team’s longtime Achilles heel.

No offense, but until Staley’s rights his inept defense the Chargers will be left behind.