Instead, Anthony Hopkins, off the back of his surprise Baftas win for his role in The Father, won over Boseman.
And Hopkins wasn't even there, or at the London satellite event. Last we heard, he was visiting his late father's grave in Wales:
Instead, presenter Joaquin Phoenix accepted the award on Hopkins' behalf before the credits rolled to a general sense of stunned bemusement.
The second Oscar for Hopkins comes nearly 30 years after his first in 1992, for playing Hannibal Lecter in The Silence of the Lambs. He's been nominated four times since without a win.
So, if anyone had suspicions that the ceremony's producers got a tip-off before the night, now we know they don't. Steven Soderbergh was as much in the dark as you were.
The twitterati, naturally, had a lot to say about the anticlimactic moment.
Not everybody saw the humour in the situation.
The big winners
Best Picture: Nomadland
Best Actor in a Leading Role: Anthony Hopkins – The Father
Best Actress in a Leading Role: Frances McDormand – Nomadland
Best Director: Chloé Zhao – Nomadland
Best Actress in a Supporting Role: Youn Yuh-jung – Minari
Best Actor in a Supporting Role: Daniel Kaluuya – Judas and the Black Messiah
Best adapted screenplay: The Father – Christopher Hampton, Florian Zeller
Best Original Screenplay: Promising Young Woman – Emerald Fennell
Best Animated Feature Film: Soul
Best International Feature Film: Another Round
Mank won three awards in the technical categories, while Ma Rainey's Black Bottom picked up two gongs for Costume and Hair & Make-up.
