The Milwaukee Bucks have successfully acquired a group of long, versatile defenders to match up with offenses that are becoming increasingly difficult to stop. Unfortunately for the players and front office, head coach Jason Kidd is letting them down with his backward defensive schemes.

Kidd was hired straight out of retirement to helm the Brooklyn Nets, and his quick ascension to the head-coaching ranks made sense. The future Hall of Fame point guard was a cerebral player who spent time on the floor during the league’s most recent—and still ongoing—evolution. As someone who grew significantly as a player, he was a natural choice to lead the young Bucks into the new NBA.

Instead, he appears to be stuck in the 1990s.

Things weren’t always this way. During his first year in Milwaukee, the Bucks finished second in defensive rating.  Sure, the offense struggled.  But that was bound to change as players matured and Kidd taught them some tricks from his playing days—and it has, though said advancement is largely a product of freakish improvement from Giannis Antetokounmpo.

The defense, however, has regressed faster than a warm Miller Lite.

During his second and third seasons, Kidd’s defenses ranked 22nd and 19th. Things have not gotten any better in 2017-18; the Bucks currently rate 22nd in points allowed per 100 possessions, which includes a slight uptick following the Eric Bledsoe trade.

Milwaukee’s defensive troubles would not be alarming, but its roster is full of talent.  With Khris Middleton and Thon Maker playing alongside Antetokounmpo, Bledsoe and Malcolm Brogdon, the Bucks have a seemingly endless supply of long, athletic and capable defenders.

That length and athleticism is being misused.

A major benefit of having that size and speed all over the floor is the ability to play a more standard defensive scheme without yielding the constant mismatches modern offenses strive to create.  While a smaller, slower team has to aggressively trap and scramble to rotate, the Bucks can switch screens and stay in position.

Antetokounmpo, Maker and Jabari Parker are quick enough to stay in front of opposing guards for short stints.  Bledsoe, Brogdon and Middleton can hold their own against bigger opponents on switches.  When teams attack those perceived mismatches, they are targeting only marginal advantages, often in low-efficiency isolation situations.

Rather than using their defensive versatility to bait opponents into inefficient possessions, the Bucks play a hyper-aggressive style that leads to numerous mistakes, trapping the pick-and-roll and swarming the ball when it gets to the middle of the court.  That’s not all bad.  After all, their defense forces turnovers at the league’s seventh-best rate.

The issues come when they don’t execute that aggressive style of play.

Trapping and scrambling requires precise execution.  The margin for error is minimal.  Decision-making and communication become more important.

And that’s fine if you have an undersized, intelligent team.  But the Bucks don’t require it. They should be letting their length and athleticism take over.  Instead, they’re predictably making mistakes, failing to communicate and conceding shots that they should not:

For three years running, the Bucks have rated terribly in defending spot-up situations.  In 2015-16 and 2016-17, they gave up the highest percentage of spot-up shots. This season, they’ve allowed the third most, and their opponents have been fourth-best in efficiency.

The effect is devastating because most spot-up possessions come in the form of three-point attempts. In an era where teams seek to repress shots from behind the arc, Milwaukee’s approach encourages them.

Watch here as Antetokounmpo goes under a screen against the Dallas Mavericks and blocks Harrison Barnes’ path to the rim.  Gary Payton II and Thon Maker abandon their counterparts instead of staying home, as an attempt to trap Barnes.  The result is a wide-open spot-up three for Yogi Ferrell:

Later in the same game, Maker attacks a pick-and-roll rather than allowing Brogdon to handle it. Tony Snell is forced to cut off Maker’s man from entering the paint, leaving the guy he’s supposed to be guarding wide open on the perimeter:

Against the New Orleans Pelicans, Antetokounmpo cuts off the sideline because he anticipates Middleton coming over the screen to help trap Jameer Nelson. Middleton doesn’t get over cleanly, which forces John Henson to concede a wide-open three to DeMarcus Cousins:

After a dribble hand-off against Portland, DeAndre Liggins, Maker and Middleton all commit to C.J. McCollum, which leaves Al-Farouq Aminu wide open for a three:

Milwaukee could easily simplify its defense in each of these situations by switching as opposed to attacking the ball-handler. Aiming for turnovers with this kind of volume only leads to poor communication and high-percentage shots.

And though all these plays resulted in above-the-break threes, Milwaukee’s bigger issue is allowing corner threes:

Over the past two seasons, the Bucks’ opponents took the second- and third-highest shares of corner threes. This year, they’re preventing more of those shots, but opponents are converting at an extraordinarily high clip.

Corner-three defense is particularly difficult when playing aggressively. Baseline defenders are often called upon to cut off penetration when opponents beat traps and double teams, leaving plenty of space to attempt one of the best shots in basketball.

Look at this play against Dallas, in which Milwaukee weakly attempts to trap the pick-and-roll. Ferrell takes advantage of the scrambling defense and drives to the middle of the court. Maker and Bledsoe don’t communicate and both commit to Ferrell, leaving Wes Matthews alone in the corner:

The destructive effects of Kidd’s overly-aggressive defensive scheme have stunted the progress of a promising Bucks roster.

The Bucks currently sit fifth in the East, but they’re only two games clear of the No. 9 seed.  Their net rating ranks 10th since Bledsoe joined, so hope exists that things are turning around. But if Kidd doesn’t fix the defense, they could flirt with missing the 2018 playoffs.

Despite the offensive improvements, the defense has remained sub-par.  Those struggles could be exacerbated when Jabari Parker returns in February.

Parker’s recovery from an ACL injury makes playing aggressive defense even more difficult.  Executing and communicating perfectly is hard enough.  Combining that with moving rapidly on a less-than-100-percent knee is nearly impossible.  Parker plays explosively, but he is unlikely to be fully mobile until next season.  If he is a regular rotation member, his limitations could hamper the defense further and ruin the post-Bledsoe surges.

The Bucks’ defensive issues will be fatal if they make the playoffs.  Defensive execution becomes more important as the game slows down and an inability to defend the three-point line is disastrous in today’s game.  Higher-quality opponents will exploit their vulnerabilities in a seven-game series.  The inability to defend at a high level will ultimately send them home unless change comes soon.

If things stay the same, Milwaukee is on its way to an early-round exit come May.  When that happens, it will be time for Jason Kidd to leave as well.

Follow Matt on Twitter @waymatth.

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Unless otherwise indicated, all stats are from NBA Math, Basketball-Reference or NBA.com and are accurate heading into games on Dec. 29.