Rex USA 1 / 10

It was a match made in pop-music heaven -- or at least it could have been if not for Madonna's judge-y comments.

On a Dec. 7 segment of "Carpool Karaoke," Madonna revealed to CBS late-night host James Corden that she and the late Michael Jackson had hooked up back in the day.

After she got him to "loosen up with a glass of chardonnay," she explained, there was "tongue-in-the-mouth kissing." Madonna, 58, also called the King of Pop "a willing accomplice."

At least until he wasn't.

An old friend of Michael's family has revealed why things didn't work out between the "Like a Virgin" singer and the "Thriller" genius.

"[Michael] told me back then that [Madonna had] spent the night at Neverland," Flo Anthony, a contributor to the New York Daily News' Confidential gossip column, told the newspaper.

"He also told me that she'd told him if they were going to start dating, she wasn't going to Disneyland, his favorite place," Flo added.

But that's not why the would-be relationship fizzled out.

"The reason their relationship didn't stick was because she did an interview on TV saying she would like him to get a new look and she wanted to get him out of those buckles," Flo said.

"He was livid that she criticized him on TV," Flo added. "I'm not sure, but I don't think he ever spoke to her again. He was mad as hell!"

MJ was Madge's date to the 1991 Academy Awards, where she performed "Sooner or Later" from the "Dick Tracy" soundtrack.

There's also an old story about how two megastars were planning to record a duet together for Michael's album "Dangerous." He reportedly approached Madonna with a song he'd written called "In the Closet." She was intrigued by the provocative title, but the collaboration fizzled when they had creative differences over the direction of the song.

It eventually made its way onto Michael's album, but with a "mystery girl" credited with the female vocals -- later revealed to be Princess Stephanie of Monaco.

After Michael's death in 2009, Madge made a moving speech in his honor at the 2009 MTV Video Music Awards. "In a desperate attempt to hold on to his memory, I went on the Internet to watch old clips of him dancing and singing on TV and on stage, and I thought, 'My God, he was so unique, so original, so rare. And there will never be anyone like him again,'" she said.

"He was a king," she added. "But he was also a human being, and, alas, we are all human beings, and sometimes we have to lose things before we can truly appreciate them."