The Miami Heat haven't exactly hidden their zone defense. They used it more than any team in the NBA, 11.6 percent of the time, per Synergy Sports. No other team reached even seven percent, but the Boston Celtics looked completely and utterly unprepared for Miami's trump card because the Heat hardly used it in the postseason.
Through the first two rounds of playoffs, the Heat did not once use zone defense, according to Synergy. This surely relieved a Boston team coming off of a seven-game war against the Toronto Raptors littered with box-and-one and triangle-and-two schemes that nearly knocked them out of the playoffs. The Heat may be a heavy zone team, but they aren't nearly that exotic. They've largely stuck to the more traditional 2-3 zone, but despite saving it for most of the playoffs, they uncorked it for 16 Game 1 possessions and doubled that total to 32 in Game 2.
Of those 32 zone possessions, 29 came in the second half. The adjustment worked wonderfully. Boston scored 60 points in the first half... and 41 in the second. Too many possessions went like this one: a lot of aimless passing on the perimeter in a desperate attempt to create shots that weren't there. Too often, Celtics found themselves with the ball at the nail, uncertain of what to do with defenders surrounding them.
The core tenant of a 2-3 zone is to protect the paint. The Heat succeeded on that front. Boston scored 32 points in the paint in the first half, but only 14 in the second. Watch what happens when Enes Kanter rolls to the basket. The top of the zone has collapsed into the paint. All five Heat defenders are below the 3-point line. Jae Crowder, one of the two defenders at the top, gets the strip. If he hadn't, Bam Adebayo was waiting at the rim, with Duncan Robinson there to help.
The theoretical tradeoff is supposed to be open shots behind the arc. That didn't materialize. The Celtics took 14 3-pointers in the first half, and 14 in the second, making only four after hitting six in the first two quarters. Does this look open to you?
It's a testament to Miami's remarkable defensive speed, and no Heat defender took their duties more seriously than Jimmy Butler, who wrecked absolute havoc on the perimeter in the fourth quarter.
On this play, Butler:
- Closes on Marcus Smart at the nail.
- Changes direction to close out on Kemba Walker's shot.
- Blows up Walker's drive.
- Challenges Jayson Tatum's pass enough to get the turnover.
There were a dozen possessions like that down the stretch, but none stood out more than the three steals that sealed the game. The first came through smart help defense. Daniel Theis screened Jae Crowder off of Walker, and with Adebayo still deep in his spot in the zone, Butler stepped in to tag his drive, but when Walker looked to pass, Butler had the presence of mind to get a hand up, deflect the pass, chase it to the sideline and save it for the fast break. Two points for Miami.
The next two both came on inbounds plays. Normally, the high-arching baseline pass onto the perimeter is conservative on the part of an offense. It comes as a concession when the preferable action towards the basket fails. But Butler refused to concede even the concession. He broke up the pass, and sure enough, two more points for the Heat.
The final steal was the cherry on top. Up five with less than eight seconds left, Butler didn't need to break up this lob attempt. But he played until the final buzzer and sealed the victory.
Butler covers so much ground from the top of the zone that its typical weaknesses don't need to apply. It allowed Erik Spoelstra to pack the paint with impunity in the second half of Game 2, and threw Boston entirely off of its game. With the unbridled commitment of their best player, the Heat all but disarmed the Celtics offense with a single adjustment.
Boston will have counters to the zone in Game 3, but there aren't obvious ones if the Heat can successfully close out on shooters without compromising their rim-protection. Floaters will be available, and more decisive ball-movement can help as well. But if Miami's athleticism and creativity continue to manifest so dynamically on defense, this is going to be a short series. The Celtics weren't confounded by a 2-3 zone. Every player and coach in the NBA has seen one before. They were confounded by a 2-3 zone run, essentially, perfectly, and unlike the more traditionally flawed rosters that use them, the Heat are led by a defensive superstar in Butler that is essentially scheme-proof. Unless the Celtics have a way of making Butler less committed and less athletic over the next several days, their offense is going to continue to struggle.