The Mavericks were never going to be a great defensive team this season. At best, they would be a “bend, don’t break” type unit that would hold water while a blistering offense led by Luka Doncic and Kristaps Porzingis did their thing.

For the first two months of the season, that happened. Dallas had an average defense paired with a historic offense. Over the last 15 games, however, that average defense has blown a tire and sputtered over a cliff. It was punctuated with a dissection Monday night at the hands of the Utah Jazz. Dallas lost 123-119, but it was much more of an ass-kicking than that score implies — the Jazz shot 59 percent from the floor, 43 percent from three and scored 54 points in the paint.

In the last 15 games, the Mavericks are giving up 115.5 points per 100 possessions, the 25th ranked defense in the entire league over that span. The Mavericks have lost four of their last five at home. Three of the four losses included disturbing defensive performances against the Jazz, Grizzlies and Suns, all of whom molly-whopped the Mavericks out of competitiveness.

On Monday night against the Jazz, the problems were on full display. Dallas has been terrible at preventing dribble penetration, guarding the pick and roll and picking up their man in transition.

I’m going to highlight the transition defense first, because it’s been something I’ve watched all season, not just during this slide. For whatever reason, the Mavericks cannot manage to get their defense in order after a made basket on most possessions. It’s the most advantageous position a defense to be in, setting up a half-court possession, yet time and time again the Mavericks are out of position and have a mismatch.

Willie Cauley-Stein just made floater off the pick and roll before the Jazz bring it up in the possession above. They run no action, no screens, no nothing. Hell, Cauley-Stein is even down the floor before his man, Tony Bradley, makes it to the three-point line. But for some reason Cauley-Stein is on Joe Ingles, a blatant mismatch. Ingles misses the three but Bradley gets an easy putback since he isn’t being boxed out by Cauley-Stein. This sort of stuff happens way too much and it’s inexcusable.

The transition defense is bad during a traditional fastbreak too.

It’s tough to stop a guard with a full head of steam when your rim protector is lagging the play, but the Mavericks had four defenders past half-court before Emmanuel Mudiay had crossed mid-court.

That should not happen! Mudiay basically scores 2-on-4. The Mavericks cannot guard the rim right now and it’s contagious.

The breaking point over the last two to three weeks has been that regardless of whatever scheme the Mavericks are running, teams are pouncing on them. At a certain point the scheme or rotations don’t matter — you just have to stay in front of your man. All the scheming in the world doesn’t really matter that much if you can’t execute basic defensive principles.

Dallas gets beat far too often in 1-on-1 situations without a ball screen. It happened again against the Jazz.

The Mavericks simply do not have enough quality defenders to keep things stable. Dallas is at their best when playing on a string, with all five guys talking and moving together as one. This has to happen because the Mavericks lack the individual talent on the defensive end to make up for lapses. If a teammate makes a mistake, you’re forcing other unequipped defenders to compensate, starting a chain reaction of bad decisions and open looks. Help defense is crucial, but it shouldn’t be a crutch. Dallas cannot continue to give up dribble penetration this easily.

To make matters worse, there’s uh, this:

Woof.

And I’m being nice and not even clipping Kristaps Porzingis’ weird defense in the pick and roll in the first half, where he was often caught in no man’s land between the ball handler and the roller. Rudy Gobert feasted off the Mavs lack of commitment to stop either end of the pick and roll.

This is likely why the Mavericks are signing Michael Kidd-Gilchrist, a no-offense wing who has the ability to play outstanding defense. It likely won’t be enough to compensate for the rest of Dallas’ defensive warts, but it’s a start. Dallas is still a playoff team but if they want to win some games and maybe even a series, the defense just has to be better. It doesn’t have to be great or even good — just better than whatever this is.