Black Sabbath fired Ozzy Osbourne in 1979, but it wasn't taken lightly. During a visit to The Bob Lefsetz Podcast, Geezer Butler opened up about the "heartbreaking" decision.

“It was heartbreaking because we'd all grown up together. We fought against the odds together,” the bassist recalled. "We performed miracles, making the band successful. And it was heartbreaking. It's like cutting your arm off.”

That being said, Butler stood by the decision and still believes it was best for everyone. “He definitely needed a change of lifestyle at the time,” he admitted. “We were all doing drugs and boozing and stuff like that, but we could still function. Whereas Ozzy, he wasn't functioning anymore. And we got this house in Bel Air to write an album. Ozzy just wasn't interested in the music that we were doing.”

He went on to say guitarist Tony Iommi initially suggested Ozzy get replaced by Ronnie James Dio. “Eventually Tony says, ‘Ozzy's got to go. He's just not interested. The band's not going to go anywhere if we keep on like this.’ And he says, ‘Actually I was a party the other night and I got talking to this guy called Ronnie James Dio, and he's got an absolutely brilliant voice, and I think we should give him a go.’”

“So Tony came to the decision to get rid of Ozzy,” Butler continued. “We hated doing it, but it had to happen for our sake and his sake. And it all worked out great in the end. And Ronnie James Dio came along… He sang to some of the stuff that we'd written and he was brilliant, absolutely just exactly what it needed. And that was the end of the Ozzy era.”

Of course, Ozzy was not happy when he got the news. “He couldn't believe it. I mean, it's like a ton of bricks coming down on him,” Butler divulged. “I mean, we had each other, but Ozzy didn't have anybody. And luckily that's when Sharon came along and saved him.”

It all worked out in the end, though, and Ozzy went on to have an extremely successful solo career that got him a second Rock & Roll Hall of Fame induction over the weekend. The original Black Sabbath members have also discussed reuniting for a final show.

Listen to the full podcast episode below.