The 45-year-old diva appeared at New York City’s Rockefeller Centre to sing her holiday classic All I Want For Christmas.
But it seemed the Grammy-award winning superstar struggled with some of the higher notes and replaced many with lower register notes.
After a video of the performance was leaked online, many took to Twitter to give their verdict.
Most agreed that Mariah’s voice seemed to have faltered a bit, while some cruelly suggested her estranged husband Nick Cannon ‘took her voice in the divorce’.
NICOLA MCLEAN 'PARTIED WITH MARIAH CAREY': "IT WAS THE BEST TIME OF MY LIFE"
One tweeter wrote: “Why can’t Mariah Carey sing anymore i’m so confused, what happened to her voice??!! [sic].”
However some users sympathised with the mother-of-two.
One user wrote: “I feel so bad for Mariah Carey… Her Rockefeller performance wasn’t good at all, but her Christmas album will forever be my fav [sic].”
Another added: “Idc [I don’t care] what y’all say. @MariahCarey is still fab & even if that wasn’t her best performance she’s been singing forever [sic].”
“Can everyone leave Mariah Carey alone and stop pretending like our vocals don’t change with age? She’s human and a legend regardless [sic].”
Earlier this year Nick, 33, defended his Mariah voice. Following their separation he said: “You know you might have an off night here and there, but she’s still one of the greatest performers and entertainers of all time, she’s not worried, we’re not worried, just going to keep pushing.”
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