Black Sabbath's Tony Iommi said he is "not at all happy" that an unauthorized 1979 rehearsal recording titled "Slapback" surfaced earlier this week. He also claimed that Ronnie James Dio, who sang on the track, also played bass, contrasting Geezer Butler's declaration that he was the one plucking the strings.

The song was uploaded by Gary Rees, the stepson of Sabbath keyboardist Geoff Nicholls and executor of the late musician's estate. Rees was also the one who previously shared a rehearsal recording of "Heaven and Hell," also from '79.

"I'm not at all happy with [Nicholls's estate releasing the song] — at all," the Sabbath leader told radio DJ Eddie Trunk on March 11 (transcription via Blabbermouth).

He continued, "And it's left a really bad taste in my mouth. At that point, when we did that, Geoff wasn't even involved in the band; I hadn't even got Geoff over at that time. That is actually Ronnie playing bass on that… And that was just in the lounge recorded on a cassette."

Earlier in the week, Butler told Trunk that "Slapback" was written before he stepped away from the band for a brief period and joked, "It's probably the reason I did leave. It was just one of those songs that didn't make the grade," and later clarified he played bass on the recording.

Iommi agreed with Butler on the notion that the track wasn't suited for release on a studio album, and said, "We had one or two things that we'd jam around on and play on and stuff, but it [wasn't] right for the album, so we didn't put it into shape; we didn't record it [properly] or anything."

Listen to "Slapback" below and read Loudwire's exclusive interview with Tony Iommi about the latest reissues of Heaven and Hell and Mob Rules here.

Black Sabbath, "Slapback"

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