MIAMI -- Quin Snyder's bags were packed in February for an overseas trip. He was going to spend time with some friends and family, see some coaches he has gotten to know over the years.

Then the Atlanta Hawks called with a job offer, to bring him on as coach.

And now Snyder's bags are packed again -- for the playoffs, starting with a trip to Boston.

Trae Young scored 25 points, Clint Capela grabbed 21 rebounds and the Hawks earned the No. 7 seed in the Eastern Conference playoffs by beating the Miami Heat 116-105 in a play-in tournament game Tuesday night.

"Our guys are trying to be the best version of ourselves at the end of the year," Snyder said. "The year's not over. So hopefully, we can take this and continue to build on it. It's one game -- but it was our game."

Dejounte Murray added 18 points for the Hawks, who avenged a five-game Round 1 loss to Miami last season and earned an East first-round matchup with the Boston Celtics that will start on Saturday.

Kyle Lowry scored 33 points -- his highest total during his two Miami seasons -- for the Heat, who will host either the Toronto Raptors or the Chicago Bulls on Friday to decide the No. 8 seed and a spot against the top overall seed Milwaukee Bucks in Round 1. The Raptors and Bulls will play Wednesday; the winner of Friday's game opens the series against the Bucks on Sunday.

Tyler Herro scored 26 for Miami, and Jimmy Butler finished with 21.

"Come Friday, we have to play the legit exact opposite of how we played tonight," Butler said.

For the Hawks, four reserves -- Saddiq Bey, Bogdan Bogdanovic, Onyeka Okongwu and Jalen Johnson -- combined for 53 points.

The Hawks improved to 3-0 all time in play-in tournament games; that's the best mark in the league, one that the New Orleans Pelicans can match when they play host to the Oklahoma City Thunder on Wednesday night.

And the Hawks earned this victory on the boards. Atlanta outrebounded Miami 63-39, including 22-6 on the offensive glass that keyed a 26-6 edge in second-chance points.

"We all understand the moment and the time of year it is," Young said. "Credit our guys for being locked in, ready and focused on the game plan."

The Hawks took two timeouts in the first 3:53 of the third quarter, as most of what was a 24-point lead at 63-39 with 2:37 left in the first half got whittled away -- and fast.

Miami cut the margin to 15 by halftime then opened the third quarter on a 16-6 run. Add it all up and it was a 27-8 run in about 7 minutes of play to get the Heat within 71-66.

But the Hawks had an answer then -- and every other time the Heat made a run. The Atlanta lead was 13 again going into the fourth, and when Miami was within six midway through the final quarter, the Hawks scored five straight to restore a double-digit edge.

And now, a team that was the East's No. 1 seed last spring is one game from elimination.

"Nothing about this season has been easy," Heat coach Erik Spoelstra said. "We're going to do this the hard way."