The singer told Jimmy Fallon about the last time he ever performed live with the Beatles star

Elton John is reminiscing about one of his favorite performances.

Speaking to Jimmy Fallon on The Tonight Show Wednesday, the "Rocketman" singer, 74, revealed one of his most cherished memories: a performance alongside the late John Lennon

After mentioning John's upcoming performance at Madison Square Garden on Feb. 22 and 23, Fallon asked the musical legend about the last time he ever performed with the Beatles singer. 

"I've always wanted to ask you this story about... John Lennon performing with you at the Garden," Fallon said. "This is post-Beatles. I think, actually, it might've been the last time he played live." 

John Lennon, Elton John
Credit: Steve Morley/Redferns

"It was." John responded. "I played on John's record, 'Whatever Gets You Thru the Night,' and sang on it too. And I said, 'Okay, if this record gets to number one, you've got to come on, play live with them.'"

He continued, "And he said, 'Okay, you're on.' And by Jove, it did get to number one, and then he had to keep his promise, which he did, at Madison Square Garden on Thanksgiving. And it was one of the most magical moments in my life."  

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The music legend went on to recall the moment Lennon appeared onstage, surprising all the fans at the Garden, which he described as "the finest place to play in the world." 

"Probably for me, the memory of him coming on stage and getting so much applause— I think all the band, and myself, were moved to tears, and it was such a wonderful occasion," he said, adding, "I don't think he'd played in New York since the Beatles at Shea Stadium." 

For John, getting to see someone like Lennon receive so much love for what would be the final time, was a truly unforgettable experience. Something everyone onstage could feel.

"It was just a magical moment in one's life to see someone so loved getting... so much acclaim," he said. "And you know, I had such a great time with John for two years, and it's one of the highlights of my life and my career."