Milwaukee’s Giannis Antetokounmpo drives past Boston’s Jayson Tatum during Game 3 of their best-of-seven series on Saturday in Milwaukee. The Bucks took a 2-1 series lead with a 103-101 win. Morry Gash/Associated Press

MILWAUKEE — Giannis Antetokounmpo found a way to get better shots and recapture his peak form just in time to help the defending champion Milwaukee Bucks regain the lead in the Eastern Conference semifinals.

But it was the Boston Celtics’ bad timing that made the difference in the end.

Antetokounmpo bounced back from a rare subpar performance by scoring 42 points and making the go-ahead basket with 44.3 seconds left in a 103-101 victory Saturday. The Bucks lead the best-of-7 series 2-1, with Game 4 on Monday night in Milwaukee.

“I know what my strengths are” Antetokounmpo said. “Just try to read what’s in front of me and just play with my instincts. Sometimes I’m going to make the right play and sometimes I’m going to make the wrong play, but as long as I play within my strengths, we’re going to be in a good place.”

The victory wasn’t secure until replays confirmed that Al Horford’s potential tying putback – capping a wild sequence after Marcus Smart intentionally missed a free throw – came just after the buzzer.

“I saw Al tip it, and I saw the red outline go off on the backboard,” Bucks center Brook Lopez said. “It was very close.”

Boston trailed 103-100 when officials determined Marcus Smart was fouled by Jrue Holiday just before attempting a potential tying 3-pointer with 4.6 seconds remaining. Smart made the first free throw, then missed the second intentionally – flinging a shot that went hard off the backboard before hitting the rim

That’s when things got wild.

Smart got the rebound, but missed his putback attempt. Boston’s Robert Williams charged toward the basket and sent the ball up and off the glass. Al Horford was waiting on the right side with a putback attempt that also went off the glass. Horford then got his own rebound and banked it in, but his final shot came just after the buzzer sounded.

“Missed it perfectly,” Smart said. “Nobody was ready, (but) our guys were. Got it up on the rim. We had a few chances at it. Just didn’t work out for us.”

The Celtics believed Smart should have had an opportunity to tie the game at the line. Celtics Coach Ime Udoka and Smart said it should have been a shooting foul on Holiday.

“Poor call, poor non-call,” Udoka said. “You can clearly see it. I saw it in person, but also on the film. It was a shot. You can tell it on the way up. Bad missed call.”

Holiday disagreed.

“Honestly, it looked like he was still facing the sideline,” said Holiday, who scored 25 points. “That’s not a shooting motion. He wasn’t facing the rim.”

Jaylen Brown led the Celtics with 27 points and 12 rebounds. Horford had 22 points, 15 rebounds and five assists.

Boston trailed by 14 late in the third quarter and was facing a 13-point deficit with less than 10 minutes left before storming back. The Celtics pulled ahead 100-99 and took their first lead since early in their third quarter on Brown’s two free throws with 1:49 remaining.

Both teams failed to score on their next possessions before Antetokounmpo put the Bucks back ahead. Antetokounmpo then blocked Brown’s driving layup attempt, leading to Holiday’s basket that made it 103-100 with 11.2 seconds remaining.

Antetokounmpo’s winning plays in the final minute highlighted his bounce-back performance.

After shooting 38.5% (20 of 52) in the first two games of this series, Antetokounmpo went 16 of 30 on Saturday. He made 62.5% of his attempts (15 of 24) from two-point range. He had 12 rebounds and eight assists to go along with his 42 points.

It was a major upgrade from his Game 2 outing, when he went 2 of 12 and scored just five points in the first half before finishing with 28 in the Bucks’ 109-86 loss.

“There’s going to be struggles, but at the end of the day, if you keep with it and you stay with it and you stay on course, you’re going to succeed,” Antetokounmpo said. “If you don’t stay on course, you’re not going to succeed. It’s as simple as that.”

Antetokounmpo made sure the Bucks weren’t thrown off course in their title defense.

TATUM’S TOUGH DAY

On a day when Brown and Horford both produced double-doubles, the Celtics still lost in part because of All-Star forward Jayson Tatum’s struggles. Tatum shot 4 of 19 overall and missed all six of his 3-point attempts before finishing with 10 points.

Tatum said his left wrist was bothering him but added that it didn’t impact his play.

“I was probably thinking a little bit too much,” Tatum said. “It all comes down to I’ve got to make better reads.”

TIP-INS

Celtics: Robert Williams went to the locker room in the third quarter after taking an elbow to the face from Milwaukee’s Bobby Portis as they tangled under the basket while pursuing the ball. Williams returned later in the third. … Reserve forward Sam Hauser, who had played two minutes in each of the series’ first two games, was unavailable Saturday due to an injured right shoulder. Udoka said Hauser took a fall in practice. “He’ll be OK long-term,” Udoka said. “It’s just something where he could be out a few weeks based on that.” … The Celtics lost despite having a major edge at the foul line. The Celtics were 28 of 33 and the Bucks 14 of 17 on free-throw attempts.

Bucks: Reserve guard George Hill played for the first time this postseason after recovering from a strained abdominal muscle. … Grayson Allen made his first career playoff start and Portis moved into a bench role. … The Bucks overcame a major free-throw disparity. The Celtics were 28 of 33 and the Bucks 14 of 17 on free-throw attempts. … Lopez had 13 points and 10 rebounds. He had totaled eight points in the first two games of this series.