While the 18-year-old is confirmed to record the now unknown track, she didn't perform it in Hollywood's Dolby Theatre last night.
Celebrities shared glimpses of Eilish's performance on their Twitter accounts, praising her for her selfless stage presence and sublime vocals.
While we'd never play favourites, one of our favourite looks of the night has to be our beloved Billie Eilish, who rocked up on the red carpet in a full on Chanel tweed suit. From Martin Scorsese sleeping during Eminem's performance to Bong Joon-Ho excitedly looking at his Oscar trophy, the 92nd Academy Award saw a lot of meme-worthy content.
A third added: "Billie Eilish singing yesterday is my new religion".
One "die hard" supporter of the Fab Four said they were "totally pissed" at the young singer for "ruining" the classic track.
Billie Eilish continues to show that desires and success haven't any age.