Imagine sitting ninth row at Billy Joel's Shea Stadium send-off concert, when suddenly Joel is talking directly to you, mid-song, from the stage, and telling you not to hit on his wife, who is seated next to you. That's exactly how celebrity chef Guy Fieri spent last Friday night in Queens, New York.

After trotting out a dapper Tony Bennett, a bloated Garth Brooks (clad in an ill-fitting Mets jersey), Aerosmith's Steven Tyler, and even The Who's Roger Daltry, Joel was just leaning into "Innocent Man" when he stopped between verses and squinted into the crowd.

"Hey! You're that chef guy from TV! I like you!" Joel exuberantly exclaimed, pointing at Fieri. "Say hi to my wife! She's a chef, too," Joel remarked of his significantly younger missus, Katie Lee Joel. As Joel's fingers went back to work, he offered one final piece of advice, with his Long Island drawl: "Just don't get too friendly, though!"

And that wasn't the only advice dispensed by the piano man. In the middle of "Always a Woman," Joel, while still playing the piano, looked down into the crowd again and said, "Are you gonna marry him?" to a couple in the audience just after the man had proposed. "Yes?" Joel said. "Congrats!" Waiting a beat, Joel quipped, "Get a prenup!" before heading right into the verse.

The last comment was particularly laughable given that Joel's ex-wife, Christie Brinkley, was sitting in the audience, singing along to every word.

And Billy, you have nothing to worry about where Fieri is concerned: the Food Network star is happily married. Might be better to pay attention to Paul McCartney, who was also in attendance. That guy can steal away any dude's chick easily!

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