Pop superstar George Michael has died of heart failure at the age of 53. This tragic Christmas Day news has prompted two legendary classic rock acts with whom he shared the stage, Elton John and Queen, to pay their respects.

Michael's publicist confirmed the news in a statement issued to the BBC. “It is with great sadness that we can confirm our beloved son, brother and friend George passed away peacefully at home over the Christmas period. The family would ask that their privacy be respected at this difficult and emotional time. There will be no further comment at this stage.”

In 1991, John and Michael teamed up to duet on a new version of Elton's 1974 classic "Don't Let the Sun Go Down on Me," which you can see below. In a new Instagram post, John declared, "I am in deep shock. I have lost a beloved friend - the kindest, most generous soul and a brilliant artist. My heart goes out to his family and all of his fans."

The following year, Michael was among the parade of superstars who joined forces for the Freddie Mercury tribute concert. He performed three songs with Queen at the event, including a showstopping take on "Somebody to Love." Tonight the group posted a video of that performance as a tribute to Michael.

Watch George Michael & Elton John Perform 'Don't Let The Sun Go Down On Me'

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