BOSTON -- Boston Celtics coach Brad Stevens enjoys seeing his former players pass through TD Garden. But he wishes they'd stop playing so well on their first trips back.

Kelly Olynyk scored a career-high 32 points, including six 3-pointers, to help the short-handed Miami Heat deal the Celtics a 90-89 loss on Wednesday night.

Olynyk, a 2013 draftee whose final season in green was highlighted by a monster Game 7 performance in Boston's triumph over the Washington Wizards in the Eastern Conference semifinals, might have trumped that performance on a night when he connected on 12-of-15 shots over 38 minutes.

After his sixth 3-pointer of the night gave Miami a 10-point lead with 4:13 to play, Olynyk could be seen confidently chirping at Boston's bench. He added a pair of driving layups and a free throw while scoring Miami's final eight points in the final 2:45.

"I blacked out. I don't remember," Olynyk said when asked about his trash talk. "I was just really emotional.

"I mean, it definitely felt kind of like a playoff game, a playoff atmosphere, for sure. That's the way Boston's crowd and fans are. They're crazy about it. But it was an emotional night, a fun night, and I'm glad we came away with a win."

The Celtics honored Olynyk for the countless hours he put into community work during his four seasons in Boston by making him the night's recipient of the Heroes Among Us award. The gesture, which included a video tribute to his charity work, clearly resonated with Olynyk.

video: Celtics honor Kelly Olynyk with Heroes Among Us award. pic.twitter.com/0uLlje4O6l — Chris Forsberg (@ESPNForsberg) December 21, 2017

"They literally save people's lives, dive in a frozen lake and rip out two kids who were playing around on a pond. So I don't know how what I did stacks up to that," Olynyk said of the typical Heroes Among Us recipients. "But it's just an honor to be a part of it. I think there's a lot of people in there who did numerous literally un-human things. I remember we would stand on the bench, and when it happens [during a] timeout you're looking up there, and it would be like, yeah, they literally ran in an abandoned building and saved, like, a group of kids or something. Or they did something and raised $2.5 million in a day for something.

"And you're like, first of all, how did they do this? Second of all, if you're running by this building, are you really running in this building? And you're like, 'These people are phenomenal human beings.' And I don't know what to say. It's almost like you're just almost starstruck when you see these people and the feats that they've accomplished. So to be listed in a group like that, it's amazing."

A few nights after old friend Jonas Jerebko helped the Utah Jazz win in Boston, Stevens lamented how former Celtics have played inside TD Garden.

Kelly Olynyk burned Al Horford and his former Celtics teammates for a career-high 32 points in Wednesday's win. AP Photo/Charles Krupa

"It's the second time in a week that one of our former players came in here and just gave it to us," Stevens said.

Celtics guard Marcus Smart put it more bluntly.

"By this point, we shouldn't be surprised. It's just the competitive nature in every last one of us," he said. "You leave a team, and you want to prove to that team that you should still be there. ... Kelly kicked our ass. Jonas kicked our ass. We let those guys do that. If this isn't a wakeup call, I don't know what is."

The Celtics endured some increasingly typical offensive lulls, particularly when leaning on reserve-heavy units. The team also had an injury scare when rookie Jayson Tatum dislocated his right pinkie while diving to the floor early in the first quarter. Tatum popped it back into place on the court, got cleared by the medical staff and returned to help Boston make a late charge.

But Al Horford improbably fouled out with 8:14 to play, and Kyrie Irving missed a pull-up jumper at the buzzer that could have stolen a win.

A baffled Horford, who got whistled for his last two fouls in a four-second span and displayed rare anger after being called for his fifth infraction, did all he could to avoid criticizing referee Marc Davis and the fourth-quarter whistles against him.

"I don't remember the last time I fouled out, to be honest," Horford said. "And never that early. That was -- I was very surprised."

Irving said his final shot "felt like it was a pretty good look, but it wasn't good enough." When quizzed about Horford's early exit, Irving playfully replied, "You trying to set me up? That was a setup if you ask me. No comment."