Watch Guns N' Roses debut new song "Absurd" live

Twenty-eight years after Axl Rose, Slash, Duff McKagan last released music together, Guns N' Roses debuted a new song, "Absurd," during a live show in Boston.

It's been five years since the trio reunited for the 'Not in This Lifetime' world tour, and they've been supposedly working on new music for much of that time.

"Some of you might have heard this under another name. But this is really kind of absurd for us to try this,” Rose said, introducing the new track. “Wasn’t that funny? And they don’t even know the joke yet. Ok, this is called ‘Absurd.’”

Nestled in the setlist between a Stooges cover and "Civil War," the fiery new track takes off in a blur before settling into a verse beneath Rose's rapid-fire vocals. Slash and Richard Fortus trade blistering solos at least three times during the sub-three-minute track.

"See? We never run out of those songs," Rose added. "That was fun. So you heard it here first: a new Guns N' Roses song."

Check out fan-shot video of the performance via the player above.

Many GNR fans pointed out that "Absurd" resembles a Chinese Democracy-era GNR track called "Silkworms," which was last performed in 2001 and did not appear on the eventual Chinese Democracy album in 2008.

Both Slash and McKagan have said that Rose was sitting atop a mountain of unreleased material when they reunited. The band has gradually been workshopping the new material in rehearsals without pressure to deliver a new record by a set date.

Slash said late last year that he was hopeful GNR would release new music sometime in 2021.