BOSTON — At least the Hawks were more competitive after halftime. That’s a low bar considering they were so bad before it, and it’s possible the Celtics just got bored with beating them down. No matter. The Hawks had to hold on to that second half as something to feel good about because there was nothing else.

Boston didn’t expose the Hawks in Game 1 of their Eastern Conference playoff series Saturday. That suggests their flaws haven’t been evident all season. A spirited victory at Miami on Tuesday in the play-in tournament did nothing to change that big picture. The Celtics, unlike the Heat, were good enough to bring all of the Hawks’ weaknesses into focus.

Before the game, Hawks coach Quinn Snyder said his players were excited to be in the playoffs. More efforts like this, and they won’t be there for long. The Celtics staggered the Hawks from the start with sharp execution and high intensity. The visitors never led after the first four minutes, trailed by 30 points at halftime and lost 112-99 at TD Garden.

“We came out that first half, and I don’t think we was really ready,” Hawks guard Dejounte Murray said. “I don’t think we was really competing and really locked in like we’ve been in practice and like we should have been. But it’s OK. It’s a long series, and in that second half, that’s who we are.”

The Hawks will need to be a lot better to make this best-of-seven series last. There never was a moment when it seemed as if the Hawks could win Game 1. Even when the score was close early, it was inevitable that the sharpshooting Celtics would start raining 3-pointers.

That happened in the second quarter, when Boston scored 45 points to take a 74-44 lead into halftime. The Celtics scored only 38 points in the second half. The Hawks still never put any real pressure on them. Murray’s driving score with 3:16 to go got the Hawks within 12 points of the lead. Celtics center Al Horford responded with a 3-pointer, and the Hawks faded to the decisive loss.

“You can’t get down that much and expect to win,” Hawks guard Trae Young said. “But we still fought, and were being aggressive in that second half, and (we’re) just trying to carry over to the second game.”

The Hawks showed all their faults in the first half. The Celtics generated quality shots by playing fast, blowing by on-ball defenders and passing to open teammates. If a good look wasn’t there early, Boston could patiently wait until the Hawks fell asleep on backdoor cuts. The Celtics scored 20 points in the paint while building a 29-18 lead after a quarter.

It was too easy for the Celtics. Everything was hard for the Hawks at the other end, especially Young.

Young missed his first six shots, including three near the basket. When Young tried getting to the rim, the Celtics blockaded him with multiple, long defenders. Young spent a lot of time pivoting in the paint, surrounded by defenders, while looking for a teammate to bail him out. There weren’t many takers.

Murray showed up. He needed 25 shots to generate 24 points. Hard to blame him for shooting that much when he was the only Hawks player creating any offense for long stretches. None of his teammates were offensive threats before the deficit got out of hand. It didn’t take long for that to happen.

The Hawks got the deficit down to 32-24 on Young’s 3-pointer early in the second quarter. The Celtics responded by outscoring the visitors 42-12 the rest of the period. After hurting the Hawks inside early, Boston made 7 of 8 3-pointers in the second quarter.

The Hawks will have to figure out a way to control at least one of Boston’s stars. Jayson Tatum was too big for Murray and too quick for De’Andre Hunter. He scored 13 points in the first quarter and finished with 25. Jaylen Brown scored 16 points after halftime to help keep the Hawks at arm’s length. He scored 10 of those points on shots in the paint.

The Hawks made only 5 of 29 3-point attempts. That prompted Young to voice the common loser’s lament in the NBA: “We got some good looks, but the shots weren’t going down.”

True but, from Boston’s point of view, the right guys were taking those shots. Young (1-for-5), Murray (0-for-6) and Jalen Johnson (0-for-2) all have been below average shooting 3′s this season. Poor shooting can be a reason why a team loses a close game. It doesn’t explain why the Hawks were down by 30 points at halftime of a playoff game.

The Celtics took it to the Hawks, who weren’t ready.

“They played great,” Snyder said. “They were the more aggressive team in a lot of ways in that first half. We need our guys to understand there’s two halves and four quarters and seven games. The mental toughness that is required to win a series in this league is tremendous.”

After what Boston did to the Hawks on Saturday, the Hawks need to worry about winning a game in this series. They’ll try again here Tuesday.