Though Lady Gaga and Metallica brought the house down at the GRAMMYs on Sunday, the performance wasn't without its flaws.
Lead singer James Hetfield's mic wasn't working and he had to share with the "Applause" singer. While the group powered through the performance like professionals, drummer Lars Ulrich revealed on The Late Late Show on Tuesday night that the reaction backstage was very different.
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"Well, in the heat of the battle you're out there you're playing when it's a technical issue you don't really know is it going to the house, is his vocals gong to the truck?" Ulrich explained. "Maybe it's the monitors, so you just gotta keep playing."
But once they got off the stage, things got heated.
"I haven't seen him like that in 20 years," Ulrich said to Hetfield. "I mean he was livid. I mean, he's aged really well and he's a pretty chill guy, but the first five or 10 minutes in that dressing room was not a lot of fun."
Ultimately, Ulrich thinks the group gave a solid performance, adding, "We fought through it, and, you know, with the fire and Gaga in my lap for a minute at one point, it was just keep going, keep going, keep going. So we just fought through it, and a lot of people said it at least made for great television."
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Ulrich added, "In 35 years we've had a few mishaps," noting one experience where his platform didn't properly rise, adding, "I spent 15 minutes playing two or three songs under the stage."
For more excitement from the GRAMMYs, watch the clip below!