Here's a head-scratcher for you to start your morning. Metallica's 1991 self-titled disc (aka the "Black Album") changed the course of the band's sonic direction, while becoming one of the highest-selling records of all time. However, an unlikely influence crept its way into the studio -- pop crooner Chris Isaak.

Two years before the "Black Album" was released, Chris Isaak released his signature single, "Wicked Game." The song was ridiculously successful, reaching far beyond the world of pop in terms of appeal. One fan Isaak managed to grip was Metallica frontman James Hetfield, and without Isaak, the "Black Album" may have turned out significantly different.

During an episode of Talk is Jericho, Fozzy vocalist and wrestling legend Chris Jericho welcomed producer Bob Rock, who produced the iconic Black Album. Rock offered some interesting perspective into the creation of  the "Black Album," including the Chris Isaak connection. “He [Hetfield] said, ‘Bob, I’ve never really sang before — I’ve just kind yelled,’” Rock recalled. “He played me a Chris Isaak record, and he said, ‘On ‘Nothing Else Matters’ and ‘The Unforgiven,’ I want to sing. How do you sing like this?‘”

Rock continues, “I said, ‘I’ll get you a great vocal sound, so you don’t have to double your vocals. What you hear in Chris Isaak’s voice is the nuances when he sings — he isn’t doubled. He’s actually performing. You perform.’ We set it up so he was comfortable and had a great vocal sound, and then he sang. Every day he got better, and he got comfortable with it. He became a great singer.”

Check out Chris Jericho's Talk is Jericho podcast below for the full interview with Bob Rock.

Talk Is Jericho Podcast Featuring Bob Rock:

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