Tony Iommi has spoken about the recent surfacing of an unreleased Black Sabbath song, expressing his disappointment that the rough demo has seen the light of day.

The track, entitled Slapback, was uploaded to YouTube last week, and hails from the Ronnie James Dio era of Black Sabbath, as the band were writing of Heaven And Hell. It was shared by the estate of Geoff Nicholls, Black Sabbath’s longtime keyboard player who also filled in on bass when Geezer Butler took time off from the band.

Iommi, speaking to Eddie Trunk on Sirius XM, expressed his displeasure with the song being shared, saying: “I’m not at all happy with [the release] – at all. And it’s left a really bad taste in my mouth. At that point, when we did that, Geoff [Nicholls] wasn’t even involved in the band; I hadn’t even got Geoff over at that time. That is actually Ronnie [James Dio] playing bass on that… And that was just in the lounge recorded on a cassette.”

Geezer Butler on Monday, also speaking to Eddie Trunk, jokingly described the song as “probably the reason I did leave. It was just one of those songs that didn’t make the grade.” He was also asked if he was playing bass on the recording, and contrary to Iommi’s comments said: “yeah, that was right before I left. It was just a one-off thing. We just jammed it and didn’t think anything more of it.”

Butler also added that “It didn’t really work,” which unlike the player behind the bass on the track, Iommi agreed with. He said: “It [wasn’t] right for the album, so we didn’t put it into shape; we didn’t record it [properly] or anything.”

You can hear the unfinished track below.

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