The singer opted for a Versace zebra-print sheer bodysuit that exposed her nude bra and black underwear beneath, pairing it with a satin black blazer.
She tied her hair up for the occasion, finishing off her look with Prada Batgirl sunglasses, a geometric diamond necklace, matching black heels, and a small purse.
Beside her on the red carpet was her fiancé Matthew Rutler, dressed in a smart black tux of his own, who couldn't keep his arms off his partner.
The 42-year-old has talked in the past about embracing more bold styles over the years as her career has progressed and she's had more agency to make creative choices.
Speaking of her debut in 1999 with Vogue's Life in Looks back in October, Christina said: "I didn't have any mobility to have a say yet, so I played it safe," embracing the cutesy girl-next-door style similarly portrayed by peers like Britney Spears and Mandy Moore despite the more adult musical themes.
She attributes her major shift in style from the conservative to the risqué to the release of her 2002 album Stripped, which has since been hailed as one of the most influential albums of the aughts.
With that particular era being defined by her dirty blonde braids and leather chaps, the mom-of-two said: "I wanted this album to embrace every different part of being a woman.
"There's such a rulebook that's handed to us [as women in music], and I was given it since I was a little girl. The older I got, the more I realized you have to stand up against it and create your own story. I wanted to go against the grain of what a pop star should look and sound like.
"I was starting to be out of my shell a little bit… That was me coming into expressing who I was."
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