Game of Zones
How much zone do NBA teams run in the 2022-2023 season?
About this time last year, I did a deep dive into zone defense in the NBA. This season, I wanted to revisit that topic — in the midst of the 2022-2023 offensive explosion, are teams turning to zone more often?
*Data per Synergy Sports and Cleaning The Glass as of Jan 17, 2023*
To summarize relevant bits of my previous article: Zone has rarely been used in the past — partially because the league outlawed zone defense until the 2001-2002 season. As a result, coaches have been slow to explore zone possibilities except on out-of-bounds plays (which are generally designed to attack man defenses, theoretically leaving them vulnerable to a good zone). Defensive three-seconds defangs most zones, and the common thought is that NBA players are too good at shooting and passing for a zone to be effective. Guarding space instead of players also makes it difficult to find the right man to box out when a shot goes up.
Because of all that, it’s generally seen as a break-glass-in-case-of-emergency deal, something that stems from desperation. The Charlotte Hornets were the only team that used zone in > 10% of their halfcourt possessions last season, and the Miami Heat and Portland Trail Blazers were the only other teams that cracked even 8%.
The Blazers and Hornets both had poor man-to-man defenses, and their zones were an attempt to find something with defensive juice.
The Heat, under Erik Spoelstra, have generally been a little more willing to use the zone from a position of strength — putting long-armed defenders at the top to harass ballhandlers and stationing weaker defenders in the corners, where their responsibilities were lighter. We talked more about their zone principles last year, so I won’t repeat myself. Toronto hasn’t used zone quite as much, but they are in a similar boat as Miami.
But generally speaking, I found that zone was rarely used and didn’t seem to be on the upswing.
Well, I’ve updated the data through this year — and it’s in a similar place:
The median team usage of zone is at 2.5% of a team’s halfcourt possessions, higher than in 2021-2022 but lower than two years prior (I added 2011-2012 as a historical frame of reference). “But wait,” you might say, “the average is the highest that it’s been in some time!”
That’s true, but misleading. In fact, the rise in the average is entirely due to one team…
The Miami Heat have taken their zone game to another level this season, using it on more than a quarter of their possessions thus far. To put this in perspective, the most any team has used zone since it became legalized was also the Miami Heat, in 2018-2019, when a whopping 13.9% of their halfcourt possessions were in zone. Those Heat used 1,053 possessions of zone that season. This year’s Miami squad, after just 45 games, has already used 1,113 possessions — a new record, with half the season still to go.
When I looked at this topic last year, I did not see a strong correlation between prevalence and effectiveness — a lot of the teams using more zone were poor man defensive teams, and their zone defenses, naturally, also gave up a lot of points.
This year’s Heat have the distinction of being both heavy zone users and surprisingly effective ones. They allow just 0.927 points per possession (PPP) when in zone, beating their mark in man-to-man defenses, where they allow 1.016 points per possession.
Erik Spoelstra’s never been afraid to muck around with a zone, but this year’s Heat have taken it to another level. If the Heat make the playoffs, I’ll be watching with a keen eye to see how effective it is against the best teams in the conference.
A few other observations:
The Hornets, under James Borrego, often resorted to a zone. Charlotte’s new/returning coach, Steve Clifford, is decidedly old-school in his defensive philosophies, and the Hornets have completely excised zone from their playbook. It hasn’t helped — the team was 18th in halfcourt defense last year and is 28th this season.
The Blazers, with Chauncey Billups at the helm, have a more encouraging story — they were dead last in halfcourt defense last year, but they’re up to 16th this year. It’ll be interesting to see if point-of-attack jailor Gary Payton II’s return reduces how often Billups turns to zone going forward. Portland’s PPP in man and zone are virtually identical.
Tom Thibodeau and Billy Donovan will die before they abandon their man-to-man defensive principles.
The Celtics, Grizzlies, and Bucks don’t play zone, either, but that’s slightly misleading. All three prefer to let their power forwards (Rob Williams, Jaren Jackson Jr., and Giannis Antetokounmpo) play free safety, or a one-man zone, to protect the rim. The Celtics and Bucks, in particular, can roll out lineups filled with impressive defenders and don’t need to rely upon zones to cover up for weak links.
I’m a little surprised Orlando doesn’t run more zone. They, like Toronto, have a ton of length at all positions, which typically lends itself to an effective zone. To be fair, they do run it at the fifth-highest rate in the league and are giving up 1.043 PPP, a below-average mark. So maybe there isn’t as much juice to squeeze there as I’d think.
I took a gander at the overall playoff numbers, too, and although they change team-by-team (the Mavs love themselves a good playoff zone), most seasons don’t show a notable increase or decrease overall.
All told, this is a lot of ado about mostly nothing. The fact remains that, despite my fervent wishes to the contrary, zone is still a nonfactor in nightly play outside the confines of The Stadium Formerly Known As FTX Arena, and there isn’t much indication that it’s making a big move.
But offenses keep getting better and better, and I like to think that some innovative coaches will come up with clever zones to fluster opposing teams not used to such chicanery. Spoelstra thinks he’s cracked the code, to an extent… we’ll see if anyone else follows suit.