Billy Joel brought out surprise guest Olivia Rodrigo at his Madison Square Garden concert.

The 'Piano Man' hitmaker, 73, was joined on stage at the world-famous venue in New York City on Wednesday night (24.08.22) by the 19-year-old pop superstar for renditions of her 2021 mega-hit ‘deja vu’ and his 80s' classic ‘Uptown Girl’.

Introducing Olivia on stage, Billy said: “I’m going to bring up another young musician. This is a very talented singer-songwriter.

“She’s very talented. I like her music and so do my kids. Please say hello to Olivia Rodrigo."

She responded: “Thank you so much for having me, Billy.

“I’m such a huge fan, and I kind of wrote this next song about you."

The 'good 4 u' hitmaker had some fun switching up the lyrics of her song with Billy accompanying her on the piano.

Olivia sang: “And I bet that she knows Billy Joel / ‘Cause you played her ‘Uptown Girl'."

She later belts: “Play her piano, but she doesn’t know / That I was the one who taught you, Billy Joel.”

The 'drivers license' hitmaker has appeared on stage alongside a whole array of artists who came before her of late.

She joined Alanis Morissette for ‘You Oughta Know’, while she jumped on stage with idol Avril Lavigne to perform 'Complicated' and Natalie Imbruglia for a rendition of 'Torn'.

And at Glastonbury in June, Olivia brought out Lily Allen for a cover of her 2008 hit 'F*** You' in response to the overturning of the Roe v Wade ruling, which has left millions of women across the US without access to legal or safe abortions.

Olivia said: "I’m devastated and terrified. So many women and so many girls are going to die because of this. I wanted to dedicate this next song to the five members of the Supreme Court who have showed us that at the end of the day, they truly don’t give a s*** about freedom. The song is for the justices: Samuel Alito, Clarence Thomas, Neil Gorsuch, Amy Coney Barrett, Brett Kavanaugh. We hate you! We hate you."

Lily, 37, could be seen swearing with her middle fingers as Olivia rhymed off the names of the justices.

She told the crowd: "This is actually my first Glastonbury and I’m sharing this stage with Lily, this is the biggest dream come true ever. But I’m also equally as heartbroken about what happened in America yesterday!"

The song - which was written by Lily and featured on her sophomore album 'It's Not Me, It's You' - was initially inspired by then-President George W. Bush, who Lily described as a "f****** a********."

Some of the lyrics include: "F***you, f*** you very very much

We hate what you and we hate your whole crew, so please don't stay in touch."