"I'm just going to have fun," he said. "I'm not going to do any dunks. I still can now and then when I'm feeling good."
Turning 55 in December, Thompson, pregame chaplain for the Heat as well as senior pastor at Jesus People Proclaim International Church in Deerfield Beach, is spending the week playing for the Explosion entry in the event at the Coral Springs Gymnasium.
The hard part is wrapping his head around how long it had been since he became the first player to join the Heat from that June 23, 1988 expansion draft.
"I can't believe it," he said. "I mean, 30 great years. And time flies. Thirty years? It's hard to count that many numbers in professional basketball and to know that I was the first player picked for that team. Man, it's something."
The difference now is Thompson no longer pushes himself to run back on offense and the dunking — save for that one moment that surprised even himself — has given way to layups delivered with two hands when jumping off both legs.
And that's when the contractors, accountants, lawyers, salesmen and retirees aren't reaching in to strip that ball away.
"I don't play much at all," he said. "I look at it a lot. I'm watching the playoffs. I'm actually glad the Heat did well. The championship for them was to make it in the playoffs, and now they're building and keep going from there."
This week is the exception, the opportunity to run up and down in the event that last year featured former Louisville coach Rick Pitino in a playing role.
Mostly, Thompson takes in the game as a fan, whether it is after leading pregame chapel at AmericanAirlines Arena or viewing from his Boca Raton home.
"I'm watching all the games," he said. "When I go to the Heat games, I'm like cringing at certain plays. And sometimes I'm like, 'I want to get out there. I want to get out there.' So you never lose it.
"I'm out here because I love the game. I want to just have some fun. A lot of guys here I know, great guys that love the game like I do."
There had been thoughts of staying with the game in some form, having won NBA championships in 1987 and '88 under then Los Angeles Lakers coach Pat Riley, who now oversees the Heat.
But then came a higher calling.
"Ministry," he said. "To me, I made that commitment to the Lord to do pastoring. And I felt if it was something locally, I could do something. But nothing opened up then. But even now, I'm looking to go to be an encourager to those young players."
To say the look of the game at the Master Championship is old school would be an understatement. But Thompson said not to count him among those who insist the game was better in his day.
"It was better in our day in the sense of the physicality," he said. "They let us play hard. That's the game on the street. But these guys, they have some talent, the three-point shooting, the athletic ability is off the chain, especially with the big men shooting the threes, driving. We didn't see a lot of that. So I enjoy watching those guys do what they do."
Thompson said he still comes across former Heat teammates Keith Askins, Glen Rice and Rory Sparrow and inaugural Heat coach Ron Rothstein, but mostly prioritizes his post-basketball commitments.
It is why it meant being away from his team for Thursday's game.
"I have a Bible study," he said. "But they'll be all right."
He paused, smiled, and said, "besides, I'm old."