The Boston Celtics have been working on their zone defense this season. Under Joe Mazzulla, the Celtics like to run a “2-1-2 Spy” when they’re looking to change their defensive structure during games.
Using a 2-1-2 zone has its advantages. Whoever is playing the “spy” can read what’s unfolding elsewhere on the floor. They can quarterback a defense, letting them know where the danger is likely to come from and how to provide resistance once that danger looks to attack the Celtics.
Not everything that makes sense on paper makes sense in reality, though. Right now, the Celtics are struggling when running their zone defense. They often find themselves out of position. You can see the players fighting what is now a natural urge to switch on contact or to pre-switch onto cutters. There’s a lack of pressure on the ball, as the defense sags off a little and invites the drive. And there’s very little resistance around the perimeter.
Against the Brooklyn Nets on Tuesday night, the Celtics went to their “2-1-2 spy” defense on multiple occasions, and once again, it proved to be a work in progress. There’s a lack of urgency in this setup. A zone thrives when everyone is operating at 100%, flying out to the ball, sliding their feet as it rotates around the perimeter, picking up cutters and letting them go as they pass from each player’s designated zone on the floor.
When watching the above clip, it feels like the players are still uncertain. They don’t want to fully commit in case they’re making the wrong decision, which, in turn, will leave the defense exposed and blow up the coverage.
That’s why you run these schemes during the regular season. Every possession the Celtics are in a 2-1-2 zone setup, they’re learning and gaining reps within the new system. It might not be easy to watch right now, but the hope is that as the defense continues to become accustomed to the zone, they become proficient at it.
Boston is clearly aiming to be ready for the playoffs and to have multiple defensive options available to them, including the 2-2-1 press, the 2-1-2 spy, a 1-through-4 switch with 5 in drop, man coverage, and a switch everything system. Some of these are further along than others in terms of the players being able to execute at a high level.
The Celtics will play the Nets again on Wednesday to complete their back-to-back. It will be their last game before the All-Star break. The Celtics will likely use some more 2-1-2 zone actions during the game. It also wouldn’t be surprising to see the frequency of that zone defense begin to increase during the season’s final third. After all, Mazzulla wanted to have curveballs available, and a reliable zone defense is certainly a curveball.
Hopefully, the Celtics coaching staff can figure out their system, and the players will become comfortable with it. For now, though, the 2-1-2 zone remains a work in progress, and for this point of the season, that’s perfectly fine.
