I had a very similar one-time experience with Charles Barkley. I was a regular at the bar at the Ritz-Carlton on Central Park South in NYC, and was introduced to Barkley by the bartender, who often connected solo diners/imbibers with each other for conversation.

We had a nice conversation about NYC, vegas, gambling, friendship, etc. along with a number of tequila shots. He was extremely down to earth while not pretending like he was anything other than a world famous former basketball player.