"I was very tempted to suit him up and my coaching staff talked me out of it because I would definitely look down and throw him in and he hasn't had a practice yet," coach Erik Spoelstra said before the Heat faced the New York Knicks.
Miller has been out all season after breaking his right thumb defending LeBron James in a preseason practice. Miller is working out again and is just waiting for the team to clear him to play in games.
He shot around Friday morning wearing a small black brace on his hand and said he was "pretty close" to making his debut.
"Whenever they put me in, I'm ready," Miller said. "Could be tonight, could be tomorrow. We'll see what happens."
The Heat signed the former sixth-man award winner in July, and he will give them a top outside shooter when he gets on the court.
Spoelstra said Miller won't need much practice, because he's been able to stay in shape during his layoff.
"Right now the responsible thing to do is get him out in practice and face some contact and see how he responds to that, and then I imagine he'll be ready to go," Spoelstra said.