Billy Joel welcomed a very special guest at his concert at Madison Square Garden Wednesday night.
Olivia Rodrigo — who mentions Joel and his hit “Uptown Girl” in her own smash single “Deja Vu” — joined the piano man himself during his show at the New York City arena.
Joel, 73, backed up the 19-year-old pop star on piano while she sang “Deja Vu” before they teamed up on — what else? — “Uptown Girl.”
“I’m going to bring up another young musician,” Joel told the crowd before Rodrigo came out, as the opening notes of “Deja Vu” played.
“This is a very talented singer-songwriter,” he said before reeling off some of the awards she’s won.
“I like her music and so do my kids. Please say hello to Olivia Rodrigo,” he said, as the crowd cheered.
“Thank you so much for having me, Billy. I’m such a huge fan and I couldn’t have written the next one without you, so thank you,” Rodrigo said, leading into their performance of “Deja Vu.”
The song, which was released last year, contains the line, “I’ll bet that she knows Billy Joel / ‘Cause you played her ‘Uptown Girl.’”
After the two finished, Joel got up from the piano and hugged Rodrigo.
He then announced they would perform “Uptown Girl,” or “the song that was referred to in the last song,” as he described it.
After they wrapped up their duet, the stars hugged again.
“Thank you, Billy. I love you,” Rodrigo said, as she hugged him once more before leaving the stage.
Rodrigo appeared overwhelmed by the appearance. She shared photos and videos on her Instagram story.
"biggest honor ever still crying thank u Billy!!!!!!" she wrote on a photo of her and Joel.
Wednesday night’s concert marked Joel’s 82nd monthly show at Madison Square Garden. He’s performed there as part of a residency which began in 2014. He has now performed a total of 128 shows at the famed venue.