Metallica’s “Enter Sandman” is easily one of the most popular and recognizable hard rock/metal songs of all time. However, producer Bob Rock wasn’t sold on the tune right away.

In an interview with GibsonTV (transcribed by Guitar World), “I remember Lars [Ulrich] saying, ‘Well, Sandman is the single.’ And I’m going, ‘What?’ To me it was like, I didn’t get it yet.”

Before you freak out, Rock has a good reason for his initial skepticism. “Because all the lyrics weren’t there. I was thinking ‘Holier Than Thou, ‘only because that kind of energy was up-tempo and that kind of works for me. What do I know? It ended up being Sandman, obviously a good choice.”

Rock, however, knew at least a little something when he was helming 1991’s Metallica (aka “The Black Album”.) Not only would it become the band’s first album to top the Billboard 200 album chart, it would go on to sell over 16 million copies in the United States alone.

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Erica Banas is a rock/classic rock news blogger who's well versed in etiquette and extraordinarily nice.