-Jim Root

The Bleacher Report series Game of Zones just wrapped up last week, tying a bow on the seven-season, NBA-themed parody of HBO’s epic (and ultimately controversial) show, Game of Thrones. However, for several reasons, the NBA is not the true “game of zones” in the basketball world (the elite skill level found in the professional ranks, league-specific rules prohibiting true zone alignments, etc.). That title has long belonged to college basketball, a sport with significantly wider gaps in talent and style thanks to the sheer volume of having 357 teams.

A month and a half ago, I wrote about five teams that underwent a major shift in their defensive approaches in 2019-20 – and to great effect for each of them. Richmond, Baylor, USC, Wyoming, and Stanford saw massive benefits from a pivot to man-to-man, helping each program ascend the national rankings. As it turns out, those teams are representative of a larger pattern throughout the sport of college basketball. Zone usage is tumbling nationwide, as the year-over-year trend line of “average time playing zone” continues to slope downwards:

On one hand, this means we’re increasingly more likely to have games blessed by Bill Raftery’s “mmmmman-to-man!” call to start each game, so that’s reason to raise our glasses.

For connoisseurs of the variety of styles that college basketball offers, though, this is concerning. The idea of college hoops homogenizing in a similar way to the NBA is off-putting; part of the charm of the sport is the wide array of options a coach can turn to, depending on the personnel he has assembled. So why is this happening?

Zone is often perceived as a crutch – how often do you hear something like, “Team X can’t match up with Team Y’s size, they should go zone,” “Team Z team lacks athletes, gotta go zone,” etc.? It’s offered as a Band-Aid, meant to cover up the wound of a glaring roster deficiency. I’m guilty of it in our 3MW season previews, sometimes wondering if a guard-heavy or athletically-limited squad should play primarily zone to compensate for such flaws.

But the best zones are the ones played by choice, rather than by necessity. Syracuse is the obvious example: Jim Boeheim reels in high-caliber athletes, often with a massive center manning the paint (7’2 Pascal Chukwu comes to mind); his patented 2-3 zone is certainly not a “because we don’t have the players to go man-to-man” kind of default decision. Unsurprisingly, Syracuse has consistently ranked highly in defensive metrics, finishing inside KenPom’s top 20 in AdjDE in eight of the past 11 seasons. So we know that, when fully committed to and done right, zone can work.

The other reason most often cited for going zone is as a change of pace, giving the opponent something else to prepare for and/or to throw off an offense that has found a rhythm against man. A standout example of this from this past season is Kansas mixing in a 2-3 wrinkle against Dayton’s juggernaut of an attack in Maui. Trying to disrupt the Flyers, the Jayhawks managed to get three stops in the second half, but two straight Jalen Crutcher corner triples via overloads quickly ended that dalliance. Of course, KU’s man-to-man defense was arguably the best in the country, so Bill Self rarely had to resort to such a curveball. That zone only saw the light of day one other time (@ West Virginia in mid-February).

Delving deeper into the numbers from the first graph shows that these “mix it up” defenses are where zone is dying. According to Synergy, in 2019-20, seven teams played some form of zone more than 75% of the time; back in 2013-14, that number was six — nothing noteworthy there. But look how sharp the decline is in teams that used it more as a tactical adjustment:

Unsurprisingly, there’s been a counteracting rise in teams playing almost exclusively man-to-man:

Here’s another visual, plotting every team’s zone usage in the 2013-14 season and the 2019-20 season onto one continuous curve. The extremes on the top end of the spectrum are the same, but it’s everywhere else that is falling:

I’ll offer three theories here. The simplest is that teams simply don’t practice zone as frequently, so coaches are hesitant to run them out in games. By their nature, coaches are creatures who enjoy control, and trusting players to run something that has not been fine-tuned over hundreds of reps is a relinquishment of control at which many may hesitate.

A more abstract hypothesis is that skill level is rising throughout the sport, rendering zones less effective. More and more players enter the college ranks with serviceable (or better) perimeter jumpers, and the continued emphasis on forwards/bigs possessing more guard-type skills opens up more routes with which to attack zones. Theoretically, this would render an “average” zone less effective than an “average” man-to-man defense. However, per Synergy, the numbers have not borne that out at all — at least until this season:

Obviously, the declining trend in zone usage started well before this season, so it may have been more of a “perception on where the game is going” decision, rather than a conclusion based on per possession data. Essentially calling coaches control freaks earlier wasn’t terribly kind, so here’s an effusive compliment: they’re incredibly smart, meaning it’s entirely conceivable that many of them saw the changes flowing through the game and opted to focus exclusively on man-to-man for that very reason. Hey, it worked out quite well for Baylor!

Finally, coaching is often a copycat profession. Tony Bennett and Chris Beard (among many others) have recently experienced wild success with their own variations of man-to-man defenses, and it’s natural for others in the business to swipe elements from Bennett’s pack line and Beard’s no-middle approach. That’s a crucial (and comforting) point, though: even as the nationwide shift to more man-to-man becomes more pronounced a wide array of styles are still available under the man-to-man umbrella. On one end of the spectrum are ultra-conservative styles like the pack line, contrasted with far more aggressive up-the-line, pressure-heavy schemes on the other end. If we’re going to have 357 teams, the least we can ask is that they don’t all play the same way.

That concludes Part 1 of this analysis – Part 2 (likely coming next week) will include a deeper dive into the implications of playing zone, as well as breaking zone usage down on a more granular level (high-majors, by conference, etc.). Check back for that soon…