The backstage farce “Birdman” topped the 21st annual Screen Actors Guild Award, winning best ensemble cast, even though its star, Michael Keaton, was upset by Eddie Redmayne in the most outstanding actor category.

Oscar favorites Julianne Moore, Patricia Arquette and J.K. Simmons cemented their front-runner status in a ceremony that often serves as a kind of preview to the Academy Awards.

Redmayne, who stars as Stephen Hawking in “The Theory of Everything,” was the somewhat surprise winner in a category expected to go to Keaton for his career-capping performance as a Hollywood has-been trying to mount a comeback on Broadway. Redmayne dedicated his award – “this very wonderful skinny man” – to sufferers and victims of ALS.

Moore, widely considered the best-actress favorite, won most supporting actress for “Still Alice,” in which she plays an academic with early onset Alzheimer’s Disease.

Accepting the award for most outstanding supporting actor for his performance as a domineering jazz teacher in “Whiplash,” Simmons thanked all 49 actors who appear in the drama.

“All of us actors are supporting actors,” said Simmons, a veteran character actor. “Each of us is essential, completely crucial to the story because if there’s one false moment, the train comes off the rails.”

“Boyhood” star Patricia Arquette added the latest in a string of awards Sunday, taking the supporting actress honor for her performance, filmed over the course of 12 years.

Sunday’s show kicked things off with a pair of wins for the Netflix prison series “Orange Is the New Black,” honoring it as best ensemble in a comedy and naming Uza Abuda most outstanding actress in a comedy series. Abuda won over a number of veteran stars, including Julia Louis-Dreyfus (“Veep”) and Edie Falco (“Nurse Jackie”).

Best ensemble cast in a drama series went to “Downton Abbey,” the second time the series has won the category.