An instrumental jam by Green Day that had been sort of hiding in plain sight has been unearthed and placed onto the internet. You can listen to the unofficially titled "That Just Happened" above.

The track was discovered by the fan site Green Day Authority, who found it in a bonus chapter of the DVD for ¡Cuatro!, the documentary about the making of their trio of 2012 albums, ¡Uno!, ¡Dos!, and ¡Tré! While the song is untitled, as far as they know, the chapter in which it appears is called "That Just Happened." The site is also speculating that the band recorded the song live in the studio in one take.

Those three records came at a difficult time for the group. Shortly before ¡Uno!'s release, singer Billie Joe Armstrong entered rehab for substance abuse issues following an expletive-filled rant at the iHeartRadio Festival in Las Vegas. The group wound up canceling its tour, and last year, Armstrong admitted that his addiction affected the albums, saying they “have absolutely no direction to them. It was about being prolific for the sake of it.”

At the beginning of March, Green Day began an arena tour in support of last year's Revolution Radio that reaches Worcester, Mass., tonight (March 17). They'll continue across North America through April 8, hit Australia in May and Europe in June. Beginning August 1, they'll begin another six-week stretch across North America at the White River Amphitheatre in Auburn, Wash. You can see all the dates and get full information at their website.

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