Katy Perry took the stage at Sunday's Grammy Awards in L.A. and, instead of performing one of her many well-known hits, she used the opportunity to debut a new song, "Part of Me" -- a ditty not-so-subtly aimed at her soon-to-be ex Brand, 36, who blindsided her last December by filing for divorce after 14 months of marriage.

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Dressed in a skin tight bodysuit, wearing a cropped, punk-blue wig, a ticked-off Perry, 27, prowled across the stage as she sang lyrics like "You chewed me up and spit me out/Like I was poison in your mouth/You took my light, you drained me down...You ripped me off, your love was cheap."

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Last week, Perry and British comic Brand signed papers to finalise their divorce in June; despite no pre-nup, Brand did not request spousal support or a share of Perry's massive earnings. Perry signed her documents with a smiley face.

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Still, an edgy Perry even tweaked the song's lyrics to make the song even more pointed at Brand. One line originally read "You can keep the dog from me, I never liked him anyway." For Sunday's show, Perry sang "Keep your diamond ring/In fact, you can keep everything...Except for me."