Two days after dropping their opening home game of the best-of-seven finals, Boston came roaring back at the TD Garden with a one-sided Game 4 blowout that squares the series at 2-2, AFP reported.
Tatum also finished with eight rebounds and five assists, with support coming from Payton Pritchard (14 points) and Derrick White (13). Jaylen Brown and Robert Williams added 12 points apiece.
Al Horford led a hard-nosed Boston defensive effort with 13 rebounds and four blocks.
Victor Oladipo led the scoring for Miami with 23 points from the bench.
None of Miami's starting line-up made double figures, making a paltry 18 points in total.
Miami coach Erik Spoelstra said his team had never been able to recover from a poor start but insisted that his team would mount a response in Game 5.
"This is part of the playoffs. There's a lot of extreme highs and extreme lows, and a lot of emotion," said Spoelstra. "You just have to stay the course and stay together.
"And it's a great series. You have to embrace that."
The game was effectively won in the first two quarters as Boston punished a strangely subdued start by Miami to race into a 29-11 lead in the first quarter.
With Jimmy Butler contributing just six points, the Heat's starters totalled 10 points in the first half, with only Oladipo's 18 points off the bench preventing a total humiliation.
The series now swings back to Florida, with top seeds Miami hosting Game 5 tonight.