Cooper Flagg Outduels Giannis Antetokounmpo as Mavericks Beat Heat 113-109, Miami Falls to 0-4

Giannis Antetokounmpo delivered his first triple-double in a Miami Heat uniform on Monday night, and it still was not enough. Cooper Flagg scored 29 points, 12 of them in the fourth quarter, and blocked a late 3-point attempt as the Dallas Mavericks rallied past the Heat 113-109 at Kaseya Center, dropping Miami to 0-4.

The Heat are 0-4 for the fifth time in franchise history and for the first time since the 2008-09 season. Antetokounmpo finished with 29 points, 15 rebounds and 11 assists, and Davion Mitchell added 21 points, but Miami let a 90-84 fourth-quarter lead slip away against a Dallas team whose depth has been tested by injuries.

How the Mavericks came back

Dallas jumped out to a 19-11 lead midway through the first quarter before Miami found its footing. The Heat closed the first quarter ahead 27-23, then pushed their advantage to 12 points in the second, their first double-digit lead of the season, when they hit four straight 3-pointers, three of them by Bobby Portis Jr. The Mavericks answered before the break and led 53-52 at halftime.

Miami led by as many as 10 in the third quarter and carried an 84-83 lead into the fourth. The Heat stretched it to 90-84 early in the final period, but Dallas tied the game midway through the quarter and then took control. A three-point play by Flagg made it 104-97 with 4:52 left, and after Bam Adebayo's dunk cut the deficit to 106-103, Flagg buried a 3-pointer for a 111-105 cushion.

Adebayo's tip-in pulled Miami within 111-109. With 31 seconds left, Andrew Wiggins rose for a 3-pointer that would have given the Heat the lead, and Flagg blocked it. Flagg's driving layup with 10 seconds remaining effectively sealed the win.

Flagg outduels Antetokounmpo

Flagg, who returned after missing Saturday's game with a sprained left shoulder, filled the box score: 29 points, six rebounds, 11 assists, five steals and three blocks. PJ Washington scored 20 points, Kyrie Irving added 18 and Walter Clayton Jr. scored 15 off the bench. It was the second win of the season for Dallas.

Antetokounmpo did most of his damage early. He had 12 points, 10 rebounds and eight assists at halftime and completed the triple-double with 8:19 left in the third quarter, assisting on a Mitchell 3-pointer. It was his first triple-double since April 11, 2025, and he became the 15th player to record a triple-double for the Heat in the franchise's 39 seasons, according to Yahoo Sports. Some box score services listed him with 14 rebounds; Yahoo Sports and CBS Miami list 15.

The milestone put Antetokounmpo in select company in Miami. Jimmy Butler holds the franchise record with 13 triple-doubles, followed by LeBron James with nine and Adebayo with eight, according to Yahoo Sports. Jaime Jaquez Jr. recorded one at Sacramento last January, with 16 points, 12 rebounds and 10 assists.

Flagg, the No. 1 overall pick in the 2025 NBA Draft and now in his second season, made the biggest plays when it mattered. Beyond his late block and clinching layup, his five steals helped Dallas turn Miami's mistakes into points in a game decided by two possessions.

Elsewhere in the Miami lineup, Adebayo scored eight points on 3-of-10 shooting. Coach Erik Spoelstra started Antetokounmpo, Adebayo, Mitchell, Wiggins and Klay Thompson for the fourth straight game.

Where it went wrong for Miami

The Heat's problems on Monday looked a lot like the problems of their first three games. Dallas won the rebounding battle 51-42, and Miami has been outrebounded 202-152 through four games, according to Yahoo Sports. The Heat have allowed at least 113 points in every game. Miami also missed 11 of its 25 free throws, CBS Miami reported, a costly total in a four-point loss.

Tempers flared as well. After Antetokounmpo was taken down by Daniel Gafford, Portis shoved Gafford. Gafford was assessed a Flagrant 1, and the two players received offsetting technical fouls.

Spoelstra called the loss disappointing. "This is not the start anybody wanted, but it's happened," he said. Mitchell was blunter about the fourth quarter: "I think we just let go of the rope."

A historically slow start

Expectations were high in South Florida after Antetokounmpo's arrival, but the losses have piled up from opening night. Anthony Edwards scored 45 points and hit nine 3-pointers as Minnesota beat Miami 131-106 in Antetokounmpo's Heat debut, a game in which he scored 35. Detroit then led wire to wire in a 128-111 win at Kaseya Center, with Antetokounmpo scoring 36 points with 12 rebounds. On Saturday, the Heat lost 115-110 at Charlotte.

Antetokounmpo has been productive throughout, scoring 35 points in the opener before fouling out, according to the Associated Press, and 36 against the Pistons. The problem has been at the other end: Minnesota made 21 of 50 attempts from 3-point range in the opener, and no opponent has been held under 113 points.

Miami's results so far:

The Heat had been 0-2 only eight times in their 39-year history before this season, according to the Associated Press. This is the fifth 0-4 start in team history and the first since 2008-09, a stretch that included NBA championships in 2012 and 2013.

What's next for the Heat

Miami gets one day to regroup before visiting the Atlanta Hawks on Wednesday, then returns home to face the Indiana Pacers on Friday. After that, the Heat head west for a five-game road trip against the Lakers, Clippers, Warriors, Kings and Jazz. The Mavericks host the Oklahoma City Thunder on Wednesday.

With the defense allowing at least 113 points a night and the rebounding gap growing, Spoelstra's rotation, including how the bench minutes behind Portis and Pelle Larsson shake out, will be under scrutiny as Miami tries to avoid falling further behind in the Eastern Conference.