She said what?! Madonna made an extremely NSFW proposition to fans during her opening act for Amy Schumer at Madison Square Garden on Tuesday, October 18.

During the comedian's New York City show, the Queen of Pop made a surprise stand-up appearance, and jokingly offered to perform a sex act on male fans if they cast their ballots for Hillary Clinton in November.

"One more thing before I introduce this genius of comedy," Madonna, 58, told the audience moments before Schumer, 35, took the stage. "If you vote for Hillary Clinton, I will give you a blow job — and I'm good!"

Giving fans a thumbs-up, the no-holds-barred entertainer added, "I take my time, I make lots of eye contact and I do swallow."

This wasn't the first time the duo shared the Madison Square Garden stage together. Last September, Schumer opened up for Madonna's Rebel Heart tour during three of her NYC stops.

After Tuesday night's show, Madonna took to Instagram to share a photo with her pal. "Love and Respect this woman so much!! Thanks for letting me get on your stage!" she captioned the shot. "It was AWESOME!! You were AWESOME!"

The Material Girl also shared a shot of herself on stage, writing, "So much fun opening up for @amyschumer at Madison Square Garden tonight!! It was short but it was sweet (like me). I'm forever changed! Love you Amy!!"

During Schumer's set, she read an open letter to Tampa, Florida, after approximately 200 Donald Trump supporters walked out of her show in the Sunshine State earlier in the week in response to her jokes about the Republican presidential nominee.

"Dearest Tampa, I'm sorry you didn't want me, a comedian who talks about what she believes in, to mention the biggest thing going on in our country right now," she unapologetically told the crowd Tuesday night. "How could I think it was OK to spend five minutes having a peaceful conversation with someone with different views? … And Tampa, I am so sorry. I shouldn't have said that he was an orange, sexually-assaulting, fake-college-starting monster. Shouldn't have said that. I will never again say that he is an orange, sexually-assaulting, fake-college-starting monster. Ever again."

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