Move over Marilyn Monroe -- okay, not really -- but you gotta hand it to Dennis Rodman for breaking out in song as a fun surprise for a guy on his 60th bday.
The man's name is Bobby, and his family tells TMZ ... they were celebrating at Casa Machado Restaurant in San Diego Saturday afternoon when they noticed the NBA legend was there, too.
We're told they asked Rodman if he'd take a pic with Bobby, but he told them he could do better than that ... and so he did.
First diplomacy, now this. Is there anything the Worm can't do?