Madonna is slamming rumors that she performed under the influence during a number of concerts in Australia in the past few days.

The 57-year-old singer took to Instagram on Monday, posting a screen grab of a lengthy message written by one of her fans who argued as to why it would be impossible for Madonna to perform drunk or high.

"The latest media onslaught against Madonna is that she's taken to bring drunk on stage, which anyone who knows anything about her knows is absolutely ridiculous," write Remington Graves, who went on to say that if the singer were drunk, there would be no way she could keep up with the complex choreography involved in her shows. "One missed cue and the entire thing is interrupted… It's called physics. It's called logic. Use it."

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Madonna echoed Graves' comments, captioned the screen grab, "Thanks for supporting me. Too bad people don't know the art of acting and playing a character. I could never do any of my shows high or drunk."

She also agreed with a comment her fan made, alleging that the rumors of Madonna getting drunk are "yet another MISOGYNISTIC attempt to undermine a highly accomplished woman's value."

"Yes underlying all of this is sexism and mysongony which proves that not only do we not get equal pay but we are still treated like heretics if we step out of line and think outside the box!" Madonna wrote.

Madonna then posted a smiling photo of her son, David, and daughter, Mercy James, which she captioned, "This is my drug. Love and Happiness!"

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Rumors about Madonna, who is currently in the middle of a protracted custody battle with her ex-husband, Guy Ritchie, were sparked by the singer's on-stage antics at two recent concerts where she was seen drinking from what appeared to be a flask, crying, riding a tiny tricycle and using what some considered to be unusually profane language.