Utah Jazz Players and Opponent Field Goal Percentage

More of this, please! (AP Photo/Alex Gallardo)

Perhaps the most fundamental defensive principle of all is Guard Your Man.

Players who cannot effectively defend their assigned offensive player are weak points in defensive armor.  Put together enough such weaknesses and the team becomes essentially defenseless.¹  Any team mucking about at the bottom of the league in defensive rating will find the root of its problems in how individual players struggle to guard their assignments.

Thanks to SportVU tracking data, it is possible to examine how Jazz players perform in this area.  Opponent field goal percentage illustrates how efficiently an offensive player shoots the ball from various distances when checked by a particular defender as compared to how that same player shoots against the rest of the league on average.  While the information isn’t perfect, it does give a useful quantitative glimpse into how specific defenders succeed or fail at hampering efficient scoring relative to the rest of the league.

I analyzed every Jazz starter as well as Rudy Gobert and Dante Exum² for the difference in OppFG% they produce within 6, 10, and 15 feet of the basket, as well as beyond the three-point line.  Then I compared that data to the starting players of every other team in the western conference, position by position, to rank individual Jazz players’ defensive prowess.³

Here is a sample chart showing the starting small forwards in the Western Conference.  The color coding represents the respective ranking of the player’s OppFG% difference at each distance as well as that of the team overall in the final column.

The chart shows that Hayward allows the player he defends to shoot above his season average from every distance on the floor, with the increase in FG% given in positive numbers.  Even so, the color coding shows that relative to the rest of the Western Conference at his position, his opponent’s increase in FG% is respectable within 10 feet while being below average beyond.

The Jazz starters (and prospective starters) chart thusly:

Several things stand out immediately.  The first, unsurprisingly, is the dreadful awesomeness of Rudy Gobert’s defense.  Even by the standards of Western Conference centers like Tim Duncan, Dwight Howard, Marc Gasol, Tyson Chandler, DeAndre Jordan, and Andrew Bogut, Gobert is elite.  If he guards someone, they shoot considerably worse than normal regardless of where they are on the court.  That his individual OppFG% difference is so universally stellar is made only more impressive by  the Jazz’s defensive vulnerability as a team.  These green-across-the-board numbers aren’t a product of a defensive unit working together to restrict centers to only poor field goal opportunities.  It’s pure Gobert effect.

The second standout observation, at least to me, is the bipolar nature of the Jazz’s front and back court respectively in regard to what areas of the floor they defend well.

All things considered, the Jazz’s front court is protecting the hoop surprisingly well.  Within 10 feet, Derrick Favors, Gordon Hayward, and even Enes Kanter all fall in the top half of Western Conference starters at their position in defending their man near the hoop.  Even Favors’ 13th place showing between 6 and 10 feet represents his holding his man below his typical shooting average from such distance.  These numbers suggest the Jazz front court protects the paint and surrounding area well – comparable to the Oklahoma City Thunder, actually.

Perhaps more surprisingly, the Jazz’s starting back court of Trey Burke and Alec Burks, lambasted this season for their poor defense, boasts surprising green ratings for their ability to influence shots on the perimeter.  That seems completely anti-intuitive given the wealth of contrary information demonstrating how much these players have struggled.  How to resolve the paradox?

One has only to look for the scorched-earth spectrum in the Jazz chart.  The Jazz back court is atrocious at keeping their men from getting exactly what they want going toward the hoop.  The point of attack against opponents primary ball handlers is routinely caving.  As a result, the front court players are trying to help, resulting in their inability to recover to the perimeter.  Jazz front court players are being sniped to death in the scramble.⁴

It’s no surprise the Kyle Lowry eviscerated the Jazz for 39 points their last meeting.  The Raptors, and Lowry in particular, are perfectly designed to shred the current Jazz defense with their incessant penetrate-to-score-or-kick offense.  When the back court man-to-man defense fails, allowing the opponent to break the paint, the Jazz’s normally sound interior defense collapses, leaving players like Patrick Patterson to score 13 points on 6 wide open shots.

It’s no wonder the front court perimeter section of the Jazz chart looks like the Great Chicago Fire.  The conflagration spread from the back court’s inability to keep their assigned offense players from feasting on the interior of the defense.

There is good reason to hope this chart can improve, however – perhaps surprisingly quickly.  The Jazz’s bipolarity of inside/outside defense is unique among the worst defenses in the west.

Notably, the Timberwolves and Lakers are defensively vulnerable across the board.  There really is no area of aptitude to build from.  Contrast that with the Jazz front court and its demonstrated ability to protect the paint.  Where no front court player on either the Wolves or Lakers holds their man to lower than average shooting within 10 feet of the hoop, both Derrick Favors and Enes Kanter accomplish this.  Add in Hayward allowing respectable increase in OppFG% on the interior, especially when compared to Andrew Wiggins or Wesley Johnson, and the Jazz have a definite defensive component already in place.

The Jazz’s defensive weakness has more to do with vulnerability in a very specific area – the back court – than overall ineptitude or, and this is essential, general personnel liabilities.  In that way, they are most similar to the New Orleans Pelicans, who have yet to leverage the interior combination of Anthony Davis and Omer Asik into even an average team defense.⁵

The Jazz defensive identity will be built from the inside out, with Gobert and Favors as its heart.  The numbers show Gordon Hayward and Enes Kanter are holding their own as well.  It’s now up to the outer ring of the battlements, up to Trey Burke, Alec Burks, Dante Exum, and Rodney Hood, to follow suit and hold the initial point of attack.  If the Jazz are beaten by a team going 23 of 49 from the perimeter (46.7%) as the Clippers did, so be it.  That allows the Jazz to smother the interior to the tune of 14 of 32 (43.8%), giving up only 18 points scored in the paint.

That’s a defensive identity that will win a lot of games.