The Celtics put a bad loss behind them and showed their championship form in a blowout of the Bucks

Jayson Tatum drives to the basket against Milwaukee Bucks' Jrue Holiday. Tatum was the star of the show as the Bucks has no answers for his offensive prowess.Aaron Gash/Associated Press

MILWAUKEE — The Celtics’ level of concern was low after they were throttled by the struggling and shorthanded Wizards Tuesday. They insisted it was just one sleepy night amid a long season, and that it would not swell.

The NBA’s top team, the Bucks, would have some say in that Thursday. But once the game began, it became clear the loss to Washington was just a blip.

Behind Jayson Tatum and Jaylen Brown, the Celtics obliterated Milwaukee from all angles, leading by as many as 49 points before finishing off a 140-99 win in which they once again resembled title contenders.

“We responded well from the jump and that’s all that I wanted and we wanted as a team, regardless of if we won tonight,” Tatum said. “Just respond and play better than we did last game.”

Brown erupted for 17 of his 30 points in the first quarter and Tatum dominated the next two by pouring in 33 of his 40. Both watched the fourth quarter from the bench because their services were no longer needed.

Just a smattering of fans remained at Fiserv Forum by game’s end. They roared when Blake Griffin missed a free throw, as one more would win them some free food. But Griffin made the second and then barked in their direction, hammering home that this would just not be Milwaukee’s night.

Both teams spent the past couple of weeks marching toward this game that figured to help determine the Eastern Conference’s top seed. But the Celtics’ unexpected misstep against the Wizards dropped Boston three games behind the Bucks with just six remaining, erasing some of the intrigue.

A Celtics loss Thursday would have officially dashed their first-place hopes, and while that ascension remains unlikely, it is still possible. Boston secured the tiebreaker, and Milwaukee still has matchups looming against the 76ers, Grizzlies and Raptors.

Among the Celtics, there is no consensus about how much securing the top spot even matters. Even after this game, Brown said it remains the goal, and Tatum pointed out that Boston will need to win road playoff games at some point regardless.

Jaylen Brown hammers home two of his 30 with this first-half dunk.Aaron Gash/Associated Press

If nothing else, though, this victory provided further evidence that winning in Milwaukee in May should not be viewed as a pipedream. Coach Joe Mazzulla was asked whether this lopsided result could have a lasting effect should these teams meet again.

“There might be, I don’t know,” Mazzulla said. “I know our confidence should come from our togetherness, our execution. It should come from the details we put into it more than anything else.”

While these Celtics have avoided extended downturns this year, they’ve also tripped over their own feet after appearing ready to soar. Before the game, Mazzulla said a win over the Bucks would mean very little if it was followed by a dud against the Jazz Friday.

He probably never envisioned such a thorough, emphatic win. But afterward he and the others doubled down on the importance of taking another step forward against Utah.

“We’re going to show how good of a team we are by the way we respond [Friday] tomorrow,” Tatum said. “That’s all that matters at this point.”

This was a particularly encouraging night for Tatum, who has been mired in a 3-point shooting slump since putting on a dazzling display during his MVP performance at last month’s All-Star game. He entered the night 14 for 60 from beyond the arc over his last seven games but poured in 8 of 10 against the Bucks.

He shot them quickly, efficiently, and with confidence. When asked what had changed in this game, he quipped that the shots had just gone in. But when he is pulverizing teams from long-range it simply brings a new dynamic to these Celtics.

Brown, meanwhile, has been on a torrid stretch for weeks. Forward Al Horford flashed a wide smile as he thought about what it was like to see the two All-Stars shining simultaneously once again.

“It’s unbelievable,” he said. “It’s so much fun just watching them. They just had a different look in their eyes, they both did. Clear-headed, making the right play every time and this was a special one for them.”

The Celtics shot 56 percent from the field and connected on 22 of 43 3-pointers (51.2 percent). The long-range shooting was excellent, but the Bucks should be more disturbed by the action closer to the rim.

Brown, Tatum and Malcolm Brogdon had little trouble blitzing past Milwaukee’s slower defenders such as Grayson Allen, Joe Ingles and Jae Crowder. The Celtics scored 56 points in the paint and would look to exploit these opportunities often in a playoff series against the Bucks.

Malcolm Brogdon scores two of his 14 points at the expense of Milwaukee's Jae Crowder during the first half of Thursday's game.Aaron Gash/Associated Press

The Celtics have had issues holding onto big leads since the All-Star break, the 28-point collapse against the Nets the most glaring example. But that was not a problem Thursday. Boston took a 75-47 halftime lead and its offense was somehow even more dominant during the third quarter. Tatum made all six of his shots, all four of his 3-pointers and scored 18 points. Boston shot 76.2 percent in the quarter.

“Outside of making shots, I thought we had a just different approach to our mindset,” Mazzulla said, “and it’s something we have to continue moving forward.”