Summer School? Celtics Trying Something New During Offseason

The Boston Celtics had the best defense in the NBA in 2021-22, riding a league-best 106.2 defensive rating to an appearance in the NBA Finals.

That defense fell off considerably in 2022-23, though. The Celtics only dropped to second in the league-wide rankings, but saw their rating drop to 110.6 as Joe Mazzulla’s defensive philosophy put more emphasis on man-to-man defense. That slowed Boston down considerably in its Eastern Conference finals loss to the Miami Heat — who deployed more zone looks.

In an effort to catch up with trends, the Celtics are using their time in the NBA Summer League to play an extensive amount of zone defense and see how it could translate to the regular season.

“We definitely want to see what it looks like and what it looks like to teach it,” Summer League coach Tony Dobbins told Gary Washburn of The Boston Globe. “If you’re going to play zone, what are your core principles and values? Are they the same as when you build a man-to-man defense? In order to do that, we have to see what it looks like. We’ve had an opportunity to do that over a few games and then we’ll see as we break that film down together, we’ll see what that looks like for us during the regular season.”

“I think we’ve got some good things on film from just this couple of games stretch.”

Celtics Summer League coach Tony Dobbins

The shift to zone has worked for the Celtics, who have mounted a number of different comebacks in their summer schedule by utilizing the new defensive philosophy. Can they play zone all the time? Well, no, it’s all about finding balance.

“I think that’s the great debate in the NBA,” Dobbins told Washburn. “With the personnel we have, the size and the length and athleticism that we have, to try to see what it looks like. What the strong points are, what the weak points are, what the vulnerable areas that teams may look to attack. I think we’ve got some good things on film from just this couple of games stretch.”

If the Celtics are able to pair a tenacious defense with what is expected to be a prolific offense, a title could be within reach in 2023-24. We’d say that makes some summertime homework worth it.