When it comes to the all-time greatest Eminem songs, "Fack" is very low on the totem pole. That didn't stop the song from somehow appearing on Em's greatest hits LP, Curtain Call: The Hits, in 2005. One of Em's lesser-known releases, the song has never been performed by the rap god, until now.

Shady headlined Lollapalooza Brazil 2016 last night (March 12) and performed the song on stage for the first time. He hinted at the debut a few days ago on Facebook posting a picture of himself writing down his set list for show. In the flick, he has the "Lose Yourself Outro" crossed out and replaced by "Fack."

The fans at the show didn't seem to mind one bit that Em deviated from the hits in order to inaugurate the overlooked track. As the Detroit MC performs the song, the crowd is past lit and seems to know every word.

The song, an odd ode to reaching the peak of sexual pleasure, was previously unreleased when it appeared on Em's greatest hits compilation which dropped over a decade ago. Besides the intro, it was the only song that was not a certified hit from the 8 Mile MC, leaving some to wonder why it was even put on the album in the first place. Apparently, it holds some type of significance to Slim.

Speaking of going back in time. Eminem recently announced he will be rereleasing his major label debut, The Slim Shady LP on cassette.

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