The Queen biopic was embroiled in controversy when Singer was fired during the production process. He has since been accused of multiple instances of sexual abuse, all of which he denies. Rami Malek, the winner of Best Actor, has previously condemned him and spoken negatively of their experience working together.
Singer kept his directing credit on Bohemian Rhapsody due to industry rules, even though it was Dexter Fletcher who swooped in to help complete it.
Still, he was not present at the Oscars, and nor was he mentioned whatsoever.
Not only did Malek refrain from mentioning him, the sound mixing and sound editing teams who stepped up to collect awards also left him out of their speeches.
John Ottman, the film’s editor, refrained from mentioning Singer too.
Ottman said: “Freddie Mercury kind of brought us all together.
“I’m so thankful for everyone coming together and trusting me. There’s too many people to thank.
“I’m looking at Rami… thank you Brian May, Roger Taylor. Thank you the hardest working producers I’ve ever worked with in my life.”
Malek said: “Graham King, Dennis O’Sullivan, everyone at Fox and New Regency, thank you guys so much.
“I may not have been the obvious choice but I guess it worked out!”
He added: “Thank you, Queen. Thank you guys for for allowing me to be the tiniest part of your phenomenal, extraordinary legacy. I am forever in your debt.
“My crew and my cast, I love you, you are my equals, my betters. I could have never been here without you.”
Bohemian Rhapsody actually won more awards than anything else last night, with four overall.
Elsewhere at the Oscars, Green Book controversially won Best Picture and Olivia Colman took Best Actress.
Catch up on all the highlights here.