The Boston Celtics were excited after being named the top seed in the Eastern Conference, but their joys were cut short on Monday night when they played the Atlanta Hawks. After being ahead by as many as 30 points in the second quarter, the Celtics lost the lead in the third quarter and were outplayed in the last few minutes of the game, which ended in a stunning 120-118 loss.

Jayson Tatum led the Celtics when they were short-handed. He scored 37 points while playing point guard. Jaylen Brown added 24 points, but he had trouble being efficient for most of the night of the game. Kristaps Porzingis and Payton Pritchard, who together scored 32 points, were the other scoring stars. The Hawks’ scoring attack was well-balanced, with all five players (Dejounte Murray, Vit Krejci, Bogdan Bogdanovic, DeAndre Hunter, and Clint Capela) scoring 10 or more points. Bruno Fernando added 13 points off the bench.

This season, the Celtics have had to deal with being short-handed many times, but tonight’s game was especially tough. Coach Joe Mazzulla chose to start the game without Jrue Holiday (dead arm) and Derrick White (hand pain), who was the Eastern Conference Player of the Week. Instead, Al Horford and Sam Hauser got the start, and Tatum and Brown led the offense against a Hawks starting group that had players who were all at least 6 feet 5 inches tall. The unusual group worked right away—Tatum (14 points), Brown (13) and Porzingis (10) all scored 10 or more points in the first quarter, giving the Celtics a 44–22 lead going into the second.

The attack kept going into the second frame. Tatum scored 20 points before the middle of the quarter, which gave the team a 30-point lead. Even though the Hawks didn’t shoot very badly, the Celtics’ attack scored so many points that it was impossible for them to keep up. But problems were on the way in the last few minutes, when the Hawks went on a run that got them close to scoring. At the break, the score was 74–56.

At the start of the second half, things went very differently for both teams. In the first few minutes of the quarter, the Hawks scored 19 points while the Celtics scored 4. This got the crowd at State Farm Arena excited as the Hawks came back to within three points of the lead, which was an amazing turn of events.

During the expected timeout that followed, Mazzulla said something that seemed to work. As soon as they got back on the court, the Celtics went on a patient, measured 8-0 run that stopped the Hawks’ momentum. Atlanta’s unusual hero answered; Krejci scored five goals in a row to bring the Hawks back within ten points. The Celtics held off the Hawks until the end of the quarter, so it wasn’t the start of another huge run, but the damage was already done. The Celtics had a 96-90 lead going into the fourth quarter, but they knew it would be hard to get the win.

And it didn’t take long for the Hawks to finish the comeback. Atlanta started the fourth quarter on a 7-0 run in the first two minutes. A three-pointer by Wes Matthews gave Atlanta the lead over the Celtics for the first time in the game. There was a three-pointer by Svi Mykhailiuk in response, but the Hawks quickly took the lead back. With eight minutes left in the game, Atlanta had an unlikely four-point lead after a 15-5 start to the quarter, which was helped by a terrible eight-second mistake from Tatum.

For the next few minutes, the teams stayed pretty close to each other. With a little less than six minutes left, Boston tied the game at 107 with a few timely baskets, including one from young guard Jaden Springer, who came out of nowhere. The Hawks called a timeout, and Murray missed two free throws. Brown made a long jumper to give the Celtics the lead again.

As the time ran out, the defenses started to stand up, which helped the Celtics and their quick-thinking unit. Slowly but surely, they stopped the Hawks’ attack and went ahead by four points after a goalie call against Capela with just over three minutes left. Hawks coach Quin Snyder, however, questioned the call. After more thought, the block was found to be legal, removing the two Celtic points from the scoreboard.

A Tatum midrange shot kept the score even as the game got close to the end. Both teams then traded free throws. With just under two minutes left, Capela missed a dunk that could have tied the game, but Bogdanovic made a pull-up three to put Atlanta ahead by one after the Celtics’ trip went off the rails. That shot opened the game up for the Hawks. In the next minute, they went on a 7-2 run that put them ahead 120–116 with nine seconds left, freezing the game.

Next, the Celtics are staying put. They will play the Hawks again this Thursday at 7:30 PM EST at State Farm Arena in Atlanta, which will be shown on NBC Sports Boston.