Jaylen Brown called their latest loss "embarrassing" as Boston Celtics coach Joe Mazzulla took full blame.
After dropping the first two games of the NBA Eastern Conference Finals at home, the second seed needed to bounce back.
The C's shot 39.8% from the field and 26.2% from three, compared to Miami's 54.3%.
The Heat won 128-102 to advance to the NBA Finals and led by 33 points. Brown, who scored 12 points, was devastated by the Celtics' loss.
The Heat won 128-102 and advanced to the NBA Finals by 33 points. Celtics' loss saddened Brown, who scored 12 points.
Mazzulla, the youngest NBA head coach, blamed himself for not having his team "ready to play."
"The most important thing is sticking together, and then I have to be better," he remarked post-game. "I need to position them better." I need to get them ready.
Tatum gave his teammates a stern message in his post-game press conference as they face a heartbreaking series loss in Game Four on Tuesday night.
Miami won again because to Gabe Vincent's postseason career-high 29 points. He said, "I don't know if surprised is the word." We played well tonight. We fought. Shots were taken. They turned over.
The next game's approach is to compete, defend, make the appropriate offensive reads, and play solid basketball. It's game one of four. We don't like three."