Robert Trujillo says Metallica's James Hetfield and former boss Ozzy Osbourne liked his approach to bass – but in different ways.

He played with Osbourne during the ‘90s before joining Metallica in 2003. More recently, Trujillo reunited with Osbourne for the Black Sabbath icon's latest solo album, Patient Number 9

“It was great to be with Ozzy again and have his energy,” Trujillo tells Revolver. “At one point, we actually jammed on some Sabbath songs. ‘War Pigs’ was one of 'em, and that was a lot of fun because [drummer] Chad [Smith] had never played a Sabbath song with Ozzy, so he was just gleaming with happiness.”

Trujillo said those good vibes were badly needed. “There was a lot of that kind of energy going on at that time,” he added, “and it was just a great place to be when everything just seemed dismal in the world at that time. So I was very thankful that we were able to have that experience together and share those moments of creativity.”

Of course, the sessions inevitably reminded Trujillo of his earlier tenure with Osbourne. “Ozzy used to tell me, ‘Rob, you know, I’m your best friend, man. I’m your best friend because I love the bass. I don’t want you to turn it down. I want you to turn it up!’” Trujillo remembered. “You know, singers never say that!

“I mean, the only other singer that’s ever said that to me was Lady Gaga when we jammed with her with Metallica – and James kinda looked over and was like, ‘What?’” Trujillo said. “James loves bass. He just doesn’t want to hear the bass when he’s trying to sing and have that kind of taking over his sonic bubble, you know.”

Trujillo also noted how the instrument is showcased in both Black Sabbath and Osbourne’s solo work: “Bass was very important to both bands, and for me as a bass player, you’re a kid in a candy shop, you know what I mean?” Trujillo said. “A lot of times people say, ‘Oh, it’s about the guitar in Ozzy’s bands.’ But no, it’s also about the bass – it’s about everything. It’s like a power trio with a great, incredibly soulful singer.”

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