SprawlBall: A Visual Tour of the New Era of the NBA

Kirk Goldsberry

Book cover

Great fun to read during the NBA playoffs. I don’t agree with everything in the book, but it’s definitely increased my enjoyment of watching games to think about KG’s assertions.

To give an overly simplified summary, the book characterizes the ways data and analytics are changing NBA basketball, much as they changed MLB baseball a decade or so ago. In particular, the book focuses on analyzing the spatial distribution of shot efficiency. (This is certainly not news to NBA teams, but rather presenting the analysis to a broader lay audience.) Briefly speaking, the most efficient shots are dunks and layups, followed by 3-pointers. In general, two-point jumpshots are inefficient. An understanding of this spatial distribution, which the NBA started recording in the early 2000s, drives much of NBA strategy today. The Golden State Warriors were the first team to effectively exploit this analysis starting around 2015, when Steve Kerr became their head coach. GS plays a “small-ball” style of basketball, focusing on 3-point shooting and spreading the defense, while eschewing a traditional center (their “center” for many seasons was Draymond Green, who is “only” 6’ 7”). Mike Dantoni’s Houston Rockets, led by James Harden, are the team that has taken this philosophy the farthest, becoming a formidable if not dominant force in the Western Conference. (As I write this, the Rockets just lost their playoff series to the Warriors.)

KG’s book strikes me as about equal parts insightful analysis and cranky get-off-my-lawnism. He is openly nostalgic for the NBA of the ‘90s, where big post-up centers and power forwards like Patrick Ewing, Hakeem Olajuwon, and Karl Malone were forces to be reckoned with, and guards like Michael Jordan shot more fadeaways. He frequently says (and the book is full of repetition) that watching catch-and-shoot 3’s is boring and that basketball is becoming a monoculture. But I have to say that it’s tough to agree with KG’s skepticism while watching the 2019 playoffs, which have been filled with incredibly good and exciting basketball. Yes, teams shoot a lot of 3-pointers. But who have been some of the most impactful players? Off the top of my head, I’d include the Bucks’s Giannis Antetokounmpo (6’ 11”, 242, probably this year’s MVP); the Sixers’ Joel Embiid (7’ 0”, 250); the Nuggets’ Nikola Jokic (7’ 0”, 250). Doesn’t exactly sound like the death of the big man to me. The thing about those three guys is that they bring a lot more than just size and post-up ability to the game. They all have great playmaking and passing ability (following in the footsteps of LeBron James), and yes, they can hit 3-pointers too. I would much rather watch any of those three guys than Shaq any day.

I also wish that KG had taken the analysis a step further to look at how a “sprawlball” offense impacts the aesthetics of possessions as a whole. Yes, it is fairly easy to say that “a catch-and-shoot three” isn’t that exciting. But the possession as a whole becomes more exciting when the team is working together to get their shooters open looks–there is a much higher premium on inspired passing in a sprawlball offense; it doesn’t take much teamwork to give the big man the rock and let him post up. Sure, a mediocre sprawlball offense will feature a bunch of guys just standing around the 3-point line waiting to get the ball, but at least in the 2019 playoffs, that hasn’t been enough to win series. In addition, my casual empiricist observation is that a higher frequency of 3-point shooting leads to larger swings in leads over the course of the game (natural because a 3-point shot has a higher variance than a 2 in terms of points outcome), which can make the game more exciting. There are more misses, but I don’t think the gap is big enough to be that noticeable (players make like 35% of 3’s and 50% of 2’s). Finally, rebounding becomes all the more important, and I think it has made the difference in several playoff games this year.

KG says that if you like basketball today, you should also be an advocate of reform, because the game has not finished changing. He sees the future as a whole league that looks like today’s Houston Rockets, only more so. I’m skeptical that this is the case. To me, the Rockets are more of an object lesson in the limits of a “pure” sprawlball style. They have taken it farther than anyone in the league, but while it’s made them a good team, it hasn’t made them dominant, despite having the league MVP to boot.

All that said, I do think some of KG’s suggestions for reforms make sense. He’s gotten a lot of attention online for his suggestion that different teams should be allowed to draw 3-point lines in different places, much like MLB parks have different “home run lines.” But I actually think some of the subtler proposals would be better ideas. One would simply be a change in officiating to allow hand-checking, which was banned in the early 2000s. KG traces the current dominance of small guards like Steph Curry to this officiating change. I think just reverting this might add more balance to the game without totally upending it. A similarly limited idea that I liked would be to create a “paint” zone in the corner-3 area, with a 3-second violation just like the lane. KG complains a lot about what he calls “rooks,” i.e. players that are just automatically sent to loiter in those corners because they are the most efficient outside shots. Watching the playoffs, I agree that there is a lot of this going on, resulting in quite a bit of 3-on-3 play. The motivation for this “paint” would be the same as in the lane, that you shouldn’t be able to just camp out in a place where points can be scored most easily. (As an aside, another benefit for me of reading this book was learning a little more about the ways NBA rules have been changed over the years in response to developments in the sport.)

Finally, I think KG’s analysis has something to offer even in the context of my own non-sports profession, financial regulation. He opines that while teams have used analytics to build their own strategy, the league is just as well positioned to use analytics to alter the rules to keep the game fair, balanced, and entertaining. I think much the same can be said for financial regulation and probably other kinds as well. Bank stress testing, where I work, does a decent job of using data and analytics to set effective rules and improve them in an iterative way. KG’s perspective shows the importance of retaining flexibility, awareness, and responsiveness in keeping rules up to date.

My Goodreads rating: 4 stars

IndieBound