By now, we all know that Metallica's performance with Lady Gaga at this year's Grammys did not go off without a hitch. The technical issues with the microphone during the performance left James Hetfield mostly inaudible for a good portion of their collaboration on "Moth Into Flame." But Metallica are one of the best when it comes to documenting the events surrounding their performances, and they've now released footage of the Grammy rehearsal with Gaga, giving fans a better idea of what the performance might have sounded like.

Prior to "Music's Biggest Night," the band worked closely with Gaga to get their performance down at the Grammys' CenterStaging Studio. As you can see in the clip above, Gaga discusses some of the choreography and stage production a bit with the guys before jumping into the track. While the singer is mostly known for her pop songs, she's expressed her love for metal and many occasions over the years and clearly is loving the chance to headbang along with the brutality of Metallica's hit song at the time of the ceremony.

A little later on, she and James Hetfield discuss how she can be added into the song and how her vocals can work off his. Gaga takes her vocals a step up from the singer and after the first try, Hetfield proclaims, "That was awesome" and credits her for making the suggestion.

"This is so exciting for me," states Lady Gaga at one point. "This is so killer. My friends are gonna hate me on Sunday." After a particularly solid take, Lars Ulrich can be heard stating, "Follow that."

Meanwhile, in other Metallica news, the group has also posted another "fly on the wall" video taking you inside the creation of their song "Lords of Summer." While the track is included with the deluxe edition of the Hardwired ... To Self-Destruct album, the cut actually preceded the disc by two years when the band was looking to add a fresh song to their stage shows.

In the video, seen below, we learn that the original working title for the song was "X-Dust." The 18-minute clip starts just three weeks shy of the 2014 Bogota, Colombia performance where the song debuted. "That thing's a monster," says Lars Ulrich upon listening to the guitar-infused playback of the song in the studio. Hetfield and Ulrich debate  on the speed of part of the song, leading to a new riff, then leave the studio along with Robert Trujillo to move over to HQ's rehearsal space to test out the change. The excitement over the new addition is clearly there, especially for Ulrich, who proclaims, "Dude, that is a f--king king s--t riff. That is f--king stupidly awesome. That may be too good."

The video then jumps ahead to 11 days before the show, this time with Kirk Hammett joining in the fun and adding some extra layering guitar-wise to the song. And finally, the band take the newly named "Lords of Summer" to the stage for the first time March 16, 2014 in Bogota. But, as we know, the journey doesn't end there. Even after finding its way into sets, the band did some polishing before the 2016 version was offered. Producer Greg Fidelman provides his input and the band record their final version as viewed in the clip. Watch it all come together in the player below.

Watch Metallica's "Making of" "The Lords of Summer"

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