Yes, Black Sabbath ( Tony Iommi, Geezer Butler and Bill Ward) fired Osbourne in 1979 over his substance abuse and an overall disinterest in doing anything with the band. They replace Ozzy with Ronnie James Dio, ushering in the "Heaven and Hell" era—and the longstanding rumor that Ozzy held a grudge against Dio. But is that true?

In an emotional essay, Black Sabbath bassist Geezer Butler reflected on playing with Ozzy Osbourne for the final time.

Geezer Butler of Black Sabbath didn't just lose a bandmate with the death of Ozzy Osbourne - he also lost a friend. In a heartfelt tribute published by The Times on Sunday (July 27) - five days after Osbourne passed away at the age of 76 - the bassist reflected on the first and last times he ever saw the late frontman.