Whenever Eminem performs onstage he rarely disappoints. On Saturday (March 12), the Detroit native headlined the 2016 Lollapalooza Brazil festival and treated fans to a rare performance of his little-known song, “Fack.”

Although widely criticized as one of his worst songs on the 2005 greatest-hits album, Curtain Call: The Hits, the 43-year-old rapper decided to perform “Fack” at the end of his live set. Apparently, prior to the show, Em posted on Facebook a picture of the set list which shows that he had crossed out “Lose Yourself Outro” and replaced it with “Fack.”

No word on why Em would perform the non-favorable track. Is he trolling his fans? Does the song mean something to him? We don't have a clue. Despite the rarity of the song, the Brazilian fans rapped along joyously to the lyrics.

In addition, Slim Shady ran through a plethora of his biggest hits during his set, including “Love the Way You Lie,” “Lose Yourself” and “Not Afraid.” He also rapped his verses from The Weeknd’s “The Hills” (Remix) and B.o.B.’s “Airplanes Part 2.”

It's been two years since Eminem ventured on a major tour. The last time Em toured was in 2014 on his collaborative trek with Rihanna. Em's concert at Lollapalooza Brazil is the first of three performances in South America. The "Without Me" rapper is scheduled to perform in Argentina on March 18 and in Chile on March 19.

Check out the videos below of Eminem at Lollapalooza Brazil 2016.

Watch Eminem Perform "Love the Way You Lie" at Lollapalooza Brazil 2016

Watch Eminem Perform "Rap God" at Lollapalooza Brazil 2016

Watch Eminem Perform "The Hills (Remix)" at Lollapalooza Brazil 2016

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