Miller, who turns 42 towards the end of the month, retired at the end of 2005 and has since worked as an analyst with TNT.
"I'm always flattered when my name is mentioned as someone who can still help an NBA team win a championship," Miller said on Wednesday.
"I've had limited discussions with Celtics management about their roster and a potential role for me. At this time, I'm enjoying my role as an analyst with TNT."
Shaq goes to Phoenix
But Miller has now been contacted by Celtics general manager Danny Ainge and coach Doc Rivers who have asked him to consider joining their revamped team in a reserve role, playing about 15 minutes per game.
"[I have] contacted Reggie and he is contemplating a comeback with us," Ainge told AP.
Miller admitted he is calling his friends and peers seeking their advice and listening to their feedback before making a decision whether to return to an 82-game season.
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