How two key Erik Spoelstra adjustments helped Heat capture Game 2 win over Celtics

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The Celtics controlled the first half of Thursday night's Game 2 against the Heat and held a 13-point lead heading into the locker room.

And then the third quarter happened. Miami steamrolled Boston with a 37-17 run over those 12 minutes, flipping that deficit into a seven-point advantage. Despite a late Celtics surge, the Heat managed to hold on for a 106-101 win, giving Miami a 2-0 lead in the Eastern Conference finals.

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"We pulled apart, and we didn't play well," Celtics coach Brad Stevens said after the loss.

While the Celtics certainly struggled throughout second half with unforced errors — they had more turnovers (12) than field goals (11) — the Heat's strategy had a lot to do with the collapse. 

So how did the Heat flip the script in Game 2? Miami coach Erik Spoelstra made two key adjustments at halftime, one on each end of the floor.

The Bam Adebayo pick-and-roll

Heat sharpshooter Duncan Robinson hit four 3-pointers in the first quarter, so the Celtics clamped down in the second and did their best to shut down any open looks. Spoelstra used the concern about Robinson's range to open the floor for several pick-and-rolls with Adebayo.

In the play below, Tyler Herro rejects the screen and drives at Enes Kanter. (Note for Stevens: Maybe don't put Kanter in the game if you're having trouble defending the pick-and-roll.) Jaylen Brown is attached to Robinson in the corner, so Adebayo has a free dive to the rim. There's the bucket, plus the foul.

Spoelstra also ran the pick-and-roll with one side of the floor cleared out. On this play, Goran Dragic and Robinson are out on the perimeter, and Jimmy Butler is in the dunker spot. Jae Crowder runs the two-man game with Adebayo, and there is no help in sight.

Adebayo got easy opportunities at the rim again and again and again. The All-Star center had more dunks (five) than the Celtics had field goals (four) in the third quarter, finishing with 15 points on 7-of-8 shooting in the period.

The fear of Adebayo getting behind the defense then opened up driving lanes. You can see here Grant Williams is unsure whether to commit to Dragic or retreat to Adebayo. His hesitation creates an opening, and that's a layup.

"Bam was really assertive in the pick-and-roll, and that kind of loosened up some things for us," Spoelstra said.

The zone defense

Miami used zone on 802 possessions during the regular season but didn't break it out in the first round against the Pacers or the conference semifinals against the Bucks. Spoelstra deployed it with great success in the second half of Game 2.

The Celtics looked extremely flustered with multiple players lacking any sort of decisiveness in terms of shooting, passing or attacking off the dribble. The Heat's zone is longer at the top than the Raptors' version, which Boston saw last round. The combo of Butler and Crowder can cause problems with their size and anticipation.

Heat players are also on a string with their movements and rotations. Even when a Celtics ballhandler got past the initial defender, there was a helper waiting and strong communication on the back line. 

In the second half, the Celtics made five shots and turned the ball over five times on 25 plays against the Heat's zone, per ESPN Stats and Info. That's how you go from a double-digit lead to down 2-0.

Spoelstra made all the right moves in Game 2. We'll see if Stevens can pull the Celtics back together and prevent Boston from falling into an insurmountable hole.