The metal legends were left searching for a replacement for percussionist Bill Ward after he was not included in the band's reunion, and producer Rick Rubin gave the drumming job to Rage Against the MAChine star Wilk.
However, Smith admits he desperately wanted to join the band to play drums on chart-topping new record 13.
He tells Billboard.com, "When Rick didn't call me for the Black Sabbath thing, I gave him a hard time about it. I was like, 'Come on!' He's like, 'No, I got Brad Wilk from Rage playing on that.' I had to tell Brad I was a little jealous, a little drummer envy that he was playing with Sabbath. But I heard the record. It's really good, f**kin' heavy as f**k. Brad did a great job, I have to say. He did a great job. The band's swingin' (sic)."