The Heat had only nine players available for the game and Dedmon was one of eight they used in the first half. He entered late in the first quarter, then was subbed out with 9:25 left in the half. That prompted an argument on the Heat sideline, and Dedmon swatted at one of the massage guns behind the bench.
The device sailed onto the court -- coming to rest about 35 feet from where Dedmon was standing -- while play was happening. Dedmon was ejected for unsportsmanlike conduct.
He had two points and three rebounds in just under 5 minutes of game action. All such incidents are reviewed, and Dedmon could also face additional disciplinary action from the team, the NBA, or both.
"We're all a bunch of gnarly personalities,'' Heat coach Erik Spoelstra said. "That part was unfortunate. Everything before that, that's the Miami Heat. That part was unacceptable.''
Dedmon has appeared in 29 games this season for Miami, all off the bench, averaging 5.9 points and 3.7 rebounds.
The Heat were without four regular starters -- Tyler Herro, Bam Adebayo, Kyle Lowry and Caleb Martin -- on Tuesday, along with reserves Duncan Robinson, Omer Yurtseven and Nikola Jovic, all because of injuries.
They still ended up winning, 112-111, capped by an NBA-record performance at the foul line.