Slash pushed Guns N' Roses into such complex new territory on "Coma" that two of his bandmates admitted they never mastered playing the song in concert.

At 10 minutes and 13 seconds, “Coma” is the lengthiest track on the Use Your Illusion albums. The song began as a “heavy guitar-riff mantra” Slash came up with when he and fellow guitarist Izzy Stradlin were living together in the Hollywood Hills for about a month in early 1989.

“It's Slash's baby ... it's his monster,” frontman Axl Rose told Kurt Loder in a 1991 MTV interview.

“The song was eight minutes long; it was just a repeating pattern that got increasingly mathematical and involved in its precision as it progressed,” Slash wrote in his 2007 memoir. “Mathematical” isn’t something typically associated with Guns N’ Roses songs, so the timing and changes “Coma” goes through left the band's two rhythm guitarists stumped.

"[‘Coma’] was a long song, wasn't it?" Stradlin remarked to RIP magazine in 1993. "I never did learn that song. What I did is, I had a chord chart onstage for the tour, because there were like 30 changes, and they didn't flow naturally for me. I think that was Slash's song more than anything, because he was more into that heavier, Metallica sort of thing. I think we only played it three times live."

Stradlin left GNR in the summer of 1991. His replacement, Gilby Clarke, told Guitar World the following year he still wasn't able to get a handle on the song. When asked what his favorite number to play live was, Clarke replied, “Oddly enough, ‘Coma.’ I really love playing it because it's different every time.”

Hear Guns N' Roses' 'Coma'

Opening with a menacing bass line and the sound of a heartbeat, which is then replicated by drummer Matt Sorum, “Coma” features a jagged and swaying guitar, frenzied at points but pulled together before it heads off the rails. Rose sings about being in a literal coma, contentedly floating into the abyss before being interrupted by alarmed medical personnel desperately trying to bring him back to life.

All the while he's being pulled back in by the voices of berating ex-girlfriends until one voice breaks through the wall of castigation and says, simply, “I love you.” Rose, out of the coma, then rattles off a stream-of-consciousness-like screed, barely coming up for air.

It took Rose some time to come up with the song's lyrics, its difficulty, in part, stemming from "Coma"'s lack of chorus. “Axl loved it, but at first it was the one song that he couldn’t come up with the lyrics for,” Slash wrote in his book. “He was very proud of his gift for lyrics, so he was pretty frustrated by it … until one night months later when the words just came to him.”

The singer echoed those sentiments during a talk with Interview in 1992, when he said it took upward of a year to come up with the words. He noted that he considered the end segment of the song, “one of the best things that I’ve ever written.” During the chat with Loder, conducted when he was still putting the finishing touches on the song, Rose went deeper, saying he drew inspiration from a stress-induced overdose he’d had a number of years before.

“I couldn't take it … and I just grabbed this bottle of pills in an argument, and just gulped them down and I ended up in the hospital,” he recalled. “But I liked that I wasn't in the fight anymore and I was fully conscious that I was leaving. I liked that. But then ... my first real thoughts though were that ‘Okay, you haven't toured enough … the record's not going to last … it's going to be forgotten, this and that – you have work to do. Get out of this.’ And I went ‘No!’ and I woke up, and pulled myself out of it.”

Rose added that he didn’t want to glorify irresponsible behavior or have listeners take it the wrong way, "[like,] go put yourself into a coma." “So, it's really tricky, and I'm still playing with the words to figure out how to, like, show some hope in there,” he said.

“Coma” was played live only a few times on the Use Your Illusions tour. One of those performances appeared on the Japanese pressing of the band’s 1999 compilation Live Era ’87 – ’93. It was even more surprising when the classic lineup reunited in 2016 and decided to add the song to their nightly repertoire.

“Right now I like performing the Chinese Democracy stuff the most, but it was really good to be doing the song ‘Coma,’” Rose said while speaking at a 2016 Q&A hosted by China Exchange. “I knew it would make Slash happy, I knew it would make fans happy and since I was sittin’ in the chair" - Rose performed some of the tour's early shows from an onstage throne after breaking a foot - "I didn't have to worry about running around and trying to breathe."

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