Black Sabbath famously gave Van Halen its first big break on tour in 1978, inviting the Southern California up-and-comers to open for them on the 'Never Say Die!' tour.

The tour proved to be a turning point for both acts. It was Ozzy Osbourne's last with Sabbath before he was fired and launched his solo career. It also put Van Halen on the world's stage for the first time, setting the band up for a legendary career.

In a new conversation with Revolver, Ozzy recalls meeting Van Halen for the first time — his impression of Eddie Van Halen (who went on to become lifelong friends with Tony Iommi) and David Lee Roth.

"[Eddie] was such a great guy. They came to our local pub and it was good fun," Ozzy recalled. "But David Lee Roth, he's lost a couple of nuts and bolts. When you meet him, it's like, 'What's wrong with him?' He's like somewhere else, you know?

Ozzy's impression of Roth echoes Sammy Hagar's own assessment of the VH cofounder. Hagar, who succeeded Roth in Van Halen in 1985, and later toured alongside him in 2002, has said that Roth was impossible to get to know, and seemed to always be either performing for people around him or isolating himself in his dressing room.

"He wasn't ever around. He hides out. You never see him," Hagar said of their 2002 tour. "He puts on this whole big front and comes out, 'I'm here. David Lee Roth is here,' and then he goes and hides again. I don't think he's happy. He's never been married; never had a relationship; never had children. It's, like, man, how do you live like that? I don't know."

Roth himself claims to have maintained a close relationship with Alex Van Halen in the years since the final Van Halen tour, but Wolfgang Van Halen has said that despite playing in Van Halen for a decade himself, he has virtually no personal relationship with Roth. More recently, Wolf has strongly suggested that Roth is the reason the rumored Eddie Van Halen tribute concert is not happening.