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Can this version of Zion Williamson dominate the NBA?
Welcome to the 30th edition of Plot the Ball for 2023.
If you missed the previous edition, you can read it here:
Many of the non-basketball fans among you will probably still have heard the name Zion Williamson at least once. (And even if you haven’t heard of him, you’ve probably seen a clip of him.) He’s one of the most interesting players currently in the NBA precisely because his path from social media phenomenon to elite professional athlete has been so fraught — and because his preferred style of play contrasts so strongly with the rest of the league.
Can this version of Zion Williamson dominate the NBA?
I’m not sure it’s possible to do good analysis of any sport without having a simple model of how its gameplay works in your head.
I’ve articulated the way I try and think about the two distinct objectives of football teams in a previous edition of this newsletter:
The nature of that sport is such that you can survive by progressing the ball upfield better than your opponent does, even if you don’t efficiently convert the resulting weight of possession into good shots.
In basketball, by contrast, advancement of the ball up the court is generally uncontested. This, together with the presence of a shot clock, means that marked possession imbalances of the type you often see in football tend not to exist.
When teams have roughly equal number of possessions, you live and die by the efficiency of the shots you create.
And almost every top offensive player in the NBA excels at creating at least one of the most prized types of scoring opportunity: three-pointers, shots at the rim and free-throw attempts.
The Oklahoma City Thunder’s Josh Giddey — who featured in another recent edition of Plot the Ball — is finding out that, for all the passing skill he possesses, elevation above the status of an NBA role player will depend on him being able to create and finish a better mix of shots for himself.
Without the threat of a viable three-point shot1 in particular, it’s incredibly difficult to function as the focal point of an effective NBA team.
And Zion Williamson — like Wembanyama, a hyped former first-overall draft pick with freakish physical characteristics — is finding out this year just how narrow that path to success is.
Up until the start of the 2023-24 season, Zion — when he was fit and healthy — was one of the few exceptions to this rule.
Despite shooting barely any three-pointers2 in his first three (injury-interrupted) seasons in the league, he was still able to efficiently generate scoring opportunities when the New Orleans Pelicans trusted him as their lead ball-handler.
How? By barrelling past the defenders who would sag off him and taking those prized shots within a few feet of the basket anyway.
It’s hard to capture in words the thrill of watching Williamson go to work3, but ESPN’s Zach Lowe gave it a good go earlier this year:
“The unicorn trope lost all meaning long ago, but Williamson is a true one-of-one. The trampoline leaping and stanchion-wobbling thunderbolts draw the hype, but it's really about Williamson's speed. He doesn't have a first step so much as a first burst that covers an implausible distance in a literal blink.”
No one has to be sold on the effectiveness of peak Zion — and, so far in 2023-24, the Pelicans have leaned on him more than ever.
His usage rate — the percentage of his team’s possessions while he’s been on the court which have finished with him taking a shot, assisting a shot or turning the ball over — is the highest it’s ever been in his career, per Cleaning the Glass.
At 31%, it’s also among the highest of any player at his position this season.
But Williamson simply hasn’t been able to create good scoring opportunities as efficiently for himself this year as he has done in the past.
By effective field goal percentage — a metric I ported over to the analysis of cricket earlier in the year, and which attributes proportionate additional credit to players for three-point field goals they make — his offensive performance has been below-average for his position.
In the three other NBA seasons he has featured in, he has been comfortably above-average among bigs by eFG%.
His 2023-24 numbers to date rank in the middle of the pack relative to all other high-usage players too — regardless of position.
Through Monday night’s games, Williamson’s eFG% of 55% ranks 11th out of the 20 players who have a usage rate of 30% or higher.
It’s obviously still very early in the season, so appraisal of players’ performances should focus on processes rather than outcomes.
Shooting slumps do happen — and Zion’s poorer-than-expected free-throw percentage4 to begin the year suggests he’s not executing these skills as well as he can.
But his underlying shot mix has also changed in concerning ways.
Williamson is getting to the rim considerably less frequently: only 66% of his shots this year have been taken from within four feet of the basket, compared to 75% last year5.
And those are being replaced by less efficient shots from midrange. 32% of his field-goal attempts so far have been taken from between four and 14 feet — up from 21% last year.
This far in his NBA career, in short, Zion has more than compensated for his lack of shooting range with his elite ability to get to the rim — again and again — while functioning as one of his team’s offensive focal points.
But, looking at his numbers so far this season, the efficiency of that trade-off for the Pelicans is open to question for the first time.
Some of it he attributed to the team’s current injury situation around Williamson, with the absence both of CJ McCollum and Trey Murphy impacting the amount of space he has to operate in.
But Vecenie also suggested something more alarming: that Zion might now be lacking some of the exceptional athleticism — specifically, his ‘vertical pop’ — that made him stand out in his early years in the NBA.
The Pelicans — and fans all over the league — will be hoping that it’s simply a case of Williamson playing himself into game shape as the season progresses.
And his performance on Monday night against the Sacramento Kings might support that theory: it was one of his most efficient of the season, scoring 26 points on 16 shot attempts and — crucially — only attempting a single field goal from further than four feet.
To emphasise again, it’s still early — and it’s not unreasonable to think that the most important aspect of Zion’s season to date is simply that he’s been able to stay on the court.
But you have to be truly special to dominate while going against the grain in a sport where the question of what constitutes the ‘optimal’ offensive approach has effectively been settled6.
For now, it remains up for debate whether this version of Zion Williamson — possibly diminished by a number of significant injuries — will ever be able to do it consistently.
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And the space that creates for you elsewhere on the court.
He took 0.7 attempts per 36 minutes; this year, he’s actually down to 0.2 per 36.
He is hitting 59% of his free throws, after shooting 71% in 2022-23. This poor return also makes his efficiency by Cleaning the Glass’s headline metric — points per shot attempt — look even worse this year, but he’s drawing fouls at a comparable rate.
In his two prior seasons — 2019-20 and 2020-21 — the equivalent figures were 87% and 81% respectively.
A couple of years ago, Zach Kram of The Ringer actually found that the correlation which previously existed between the quality of a team’s shots and their eFG% had all but disappeared. But as Ben Falk — founder of Cleaning the Glass — told him for the piece, this is because: “[t]he league is becoming more homogenous in shot selection based on location, which means location is telling us less than it used to”.