We live in a brave new era in the NBA. Once post-ups and the mid-range ruled the day, and now the whole league is predicated on finding ways to generate more 3-point shots. With the realization that three points are 50% more than two, the post-up has gone the way of the dinosaur and the mid-range is proficiently used by only a handful of elite players.
As teams evolve the way they approach offense, defense has followed behind at a slower rate of development. The NBA’s top offense (the Dallas Mavericks) had an offensive rating of 115.9 this season, but as recently as 2014-15 the top offense (that of the LA Clippers) had an offensive rating of just 111.6. This season the Detroit Pistons had an offensive rating of 108.8, which was 20th in the NBA, but in 2014-15 it would have been the fifth-best offensive rating.
The NBA has come a long way from an offensive perspective, and is less progressive on the defensive side of things. Teams still generally use the pick-and-roll to generate offense, whether they’re trying to get 3-pointers or shots at the rim, and while defenses have indeed developed various tactics like drop coverage, the offense still has the upper hand.
There has been one surprising development over the past two years, however, and it’s one that the Detroit Pistons may need to lean in on next season: The best defensive teams give up a ton of 3-point attempts.
Make no mistake, this is a completely revolutionary twist. In 2017-18, the Sacramento Kings gave up the most 3-pointers (32.9 per 100 possessions) and they had the fourth-worst defensive rating in the league at 110.4. In 2018-19, the Milwaukee Bucks gave up the most 3-pointers (34.9 per 100 possessions), and they had the best defensive rating in the NBA at 105.0.
This season the Bucks gave up even more 3-pointers, 37.1 per 100 possessions, and their defensive rating actually DROPPED to an incredible 102.4. The NBA is a copycat league, and as a result several other top defenses followed suit.
The Toronto Raptors actually rewrote the book on 3-pointers allowed, giving up an NBA-record 38.2 3-pointers per 100 possessions (only four teams in the whole league took more 3s per 100 than the Raptors allowed), and they had the second-best defense in the NBA.
Four of the top five defenses in the NBA (the Bucks, the Raptors, the Clippers and the Boston Celtics) allowed more than 34.7 3-pointers per 100 possessions, and that would have been an league record before last season.
So where’s the logic in giving up more 3-pointers, considering that’s what offenses want?
Behind The Revolution
As it happens, teams don’t just want 3-pointers, they want 3-pointers and dunks and layups. Three might be more than two, but a high-efficiency two is even best, especially because that’s the region of the floor where offenses can draw fouls and and-1 free throw opportunities.
To some degree, all those threes are to set up shots at the rim. The league average for 3-point shooting is 35.7%, which means that the expected value of a typical 3-point attempt is 1.074 points, whereas a shot inside the restricted area has a 58.2% success rate. That’s 1.164 points per attempt on average without even factoring in additional free throw points, and this adds up over the course of a couple dozen attempts.
While the Bucks give up plenty of 3-pointers, it shouldn’t come as a surprise that they give up only 24.2 shots in the restricted area per game, and both the Boston Celtics (25.9) and Toronto Raptors (26.3) are in the top-six at preventing shots at the rim. In essence, they give up lots of the second-most valuable shot in order to completely shut off access to the shot that is truly most valuable.
This is evil scientist, Jedi mind trick stuff, and it’s easy to see it as an anomaly until you dig in a bit and see these other great defensive squads follow suit.
Of course, the key to being able to pull this strategy off is to have a great rim protector, and the Bucks have an embarrassment of riches between Giannis Antetokounmpo and Brook Lopez, and the Raptors to a similar (but lesser) degree with Serge Ibaka and Marc Gasol.
How The Detroit Pistons Can Jump On The Wave
The Detroit Pistons are on the complete opposite end of the spectrum from what the Bucks and Raptors try to accomplish. This season, the Pistons allowed the second-fewest 3-pointers at 30.0 per 100 possessions, but they didn’t reap the benefits that you would think come with this supposed perimeter defensive responsibility. Instead, they finished with the eighth-worst defensive rating at 112.4.
Using 2017-18 as a reference point, before the Bucks changed the game, the worst defense in the NBA that season had a defensive rating of 112.0.
It’s worth noting that the Pistons don’t currently have personnel that can be deployed in a fashion that would allow them to shut down the paint, but that’s going to need to be a high priority in free agency. A rim protector could enable them to further modernize their own defense as they have attempted to bring their offense into today’s game.
This season the Pistons allowed the 11th-most shots in the restricted area at 29.2 per game (5.0 more than the Bucks) and opponents shot 65.8%, sixth-worst in the NBA.
Where they did thrive this season was getting opponents to shoot from the non-restricted paint, where they allowed 16.2 per game (the Bucks allowed 16.1). The league average from that region is just 42.4%, so teams settling for that shot is a huge win. They also allowed 12.5 mid-range jumpers per game (the Bucks allowed 14.4), and league average from that region is 40.0%.
This gameplan is far from a solved equation, but the logic is sound. The NBA is headed in this direction, and keeping up with the rest of the league as they improve tactically is imperative for teams like the Pistons as they struggle to stay afloat.
Assuming the Pistons are intending to move in step with the rest of the league, expect them to sign at least one strong rim protector in free agency (or acquire via trade) and don’t be surprised when opponents let the 3-pointers fly.