Slash posted a brief TikTok video on Thursday of Guns N’ Roses rehearsing a rare — and as-yet-unreleased — song called “Hard School.”

The low-fidelity, bite-sized clip was filmed by Slash’s girlfriend, Meegan Hodges, during the band’s soundcheck at Chicago’s Wrigley Field. It showcases a heavy guitar riff and some stomping, open hi-hat drumming. Bassist Duff McKagan, drummer Frank Ferrer and keyboardist Melissa Reese are also visible, with no appearances from frontman Axl Rose, keyboardist Dizzy Reed or guitarist Richard Fortus.

You can watch the video below.

Slash didn’t reference the song by name on TikTok — and Guns N’ Roses didn’t play it during their Chicago concert, according to — but numerous fans identified the song as “Hard School” (or, depending on your preferred spelling over the years, “Hardskool” and “Hard Skool”).

The soundcheck teaser arrives days after fan-generated rumors circulated online that the reunited band was planning to release “Hard School” soon. This is one of several demos from Guns N’ Roses’ 2008 LP, Chinese Democracy, that subsequently leaked online. "But you had to play it cool, had to do it your way,” Rose sings on the up-tempo hard-rock tune. “Had to be a fool, had to throw it all away.”

If “Hard School” is officially released, it will follow Guns N' Roses’ recently issued (and live-debuted) single “Absurd,” which originated as a Chinese Democracy outtake called “Silkworms.”

Chinese Democracy was reportedly envisioned as a trilogy project — and as Billboard reported in 2018, 60 or so songs were at least partially finished upon the original release. An unnamed source noted, "All of the material that hadn't been released was coming out in 2016, then, the reunion happened.”

Meanwhile, Guns N Roses announced Thursday that they’ve postponed 2021 Mexican tour dates to next year “due to government shut down of large gatherings and COVID restrictions.”

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