Guitarist Tony Iommi talked about their frontman Ozzy Osbourne’s departure from Black Sabbath during his recent interview with BBC Radio and discussed Ronnie James Dio’s contribution.

During the late ’70s, the personal problems between Black Sabbath members started to arise due to creative differences and their then-addiction to alcohol and drugs. The tensions increased when Ozzy Osbourne left the band for three months to focus on his own project, ‘Blizzard of Ozz.’

Also, Black Sabbath’s recording sessions turned into a battle between Osbourne and Iommi, and the lead guitarist came out victorious. In 1979, the band members fired the frontman because of his excessive alcohol and drug consumption, but Osbourne insisted he wasn’t worse than the other members.

The band hired Rainbow vocalist Ronnie James Dio as their new lead singer, and Iommi described this process as exciting but frightening because they had to preserve their success following the original frontman’s departure. The guitarist stated that they changed the way they wrote and composed after Dio joined them to create a harmonious atmosphere.

In Iommi’s words, he said:

“Yeah, the Sabbath story is a weird story. Really, the number of times we had with Ozzy and he left, and he came back, and with Ronnie – he left and came back – Tony Martin left and came back, Bill left and came back, Geezer left for a little bit and came back…

Funny old round over the years. From Ozzy to Dio, when we had Dio, we realized we had to really work hard at it again, which was great at what we wanted to do. We knew we could go out and do stadiums, big venues, and we sort of got used to it.”

He went on:

“When Ozzy went, and we had to find another singer, it was again almost exciting but frightening because then we had to prove ourselves again but bringing Ronnie in was a different move altogether.

The songs became of different sound because of the way we were writing with Ozzy, we were writing differently with Ronnie. That worked, and it was good for us, and good for Ozzy as well because he had a solo career, and he went on to do great things.”

You can check out the interview below.