Birdman, a satirical film about acting in the unforgiving world of show business, won top honours from Hollywood’s actors on Sunday in an important show of support for its march towards the best picture Oscar.

The actors from Birdman won the best ensemble cast in a motion picture from the Screen Actors Guild the day after the film from Mexican director Alejandro G. Iñárritu prevailed at the Producers Guild awards.

While the Screen Actors Guild award for the best ensemble cast does not always translate to a best picture win at the Academy Awards, it does indicate that actors, the largest voting bloc for the Oscars, favour it over another strong contender, the coming-of-age tale Boyhood.

Michael Keaton, whose own uneven career trajectory mirrors the travails of Birdman protagonist Riggan Thomson, said he was sure the 100,000 SAG members found a kindred spirit in the film.

I think actors loved this movie for showing the courage the actors had, going out there and laying it out on the line

“I think actors loved this movie for showing the courage the actors had, going out there and laying it out on the line,” Keaton said backstage. “I think that is why respectfully they thought as a group we deserved to win the prize.”

Birdman could cement its front-runner status for the February 22 Academy Awards if it takes the top Directors Guild Award in two weeks.

The individual acting Oscars appear to be sewn up after the SAG awards, which went to the four artists who won Golden Globes two weeks ago – Julianne Moore, Eddie Redmayne, Patricia Arquette and J.K. Simmons.

SAG members prized lead performances by two actors portraying extreme illness.

Moore won best actress for her role as a woman with early-onset Alzheimer’s in Still Alice, while British actor Redmayne took best actor for his portrayal of physicist Stephen Hawking, disabled by motor neuron disease, in The Theory of Everything.

Boyhood, from director Richard Linklater, was believed to be a favourite for the Oscar best picture just days ago as support at the Academy swelled for his tenacious project – filming a boy’s life over 12 years with the same actors and with little backing from Hollywood.

Arquette won the best supporting actress trophy for her role as the loving single mother, her first SAG in six nominations.

“This little movie is not about the most exceptional person on earth ... this movie is about human beings and bringing real life on to the screen,” Arquette said backstage.

Simmons, an actor with a long resume in television and film, was honoured for his portrayal as the intense music teacher of a young jazz drummer in the independent film, Whiplash.

In the television awards, it was a particularly strong night for streaming company Netflix Inc. Its women’s prison comedy, Orange is the New Black, won best comedy ensemble and best actress for Uzo Aduba.

Kevin Spacey won best actor in a drama series for his conniving congressman Frank Underwood in the political thriller House of Cards.

But it was also a big night for recognizing diversity in Hollywood, a much debated topic this awards season, with black actresses taking two of the top acting honours.

In addition to Aduba, Viola Davis won best actress in a drama series as the lawyer in How to Get Away with Murder.

“I love you guys so desperately, so much,” Aduba told her fellow cast members as she accepted her first SAG award from her first nomination. “This is not done without you at all.”

Downton Abbey, the British period series that airs on PBS, won best drama series cast.

The Screen Actors Guild gave its lifetime achievement award to Debbie Reynolds, the wholesome star of musicals like Singin’ in the Rain and a staple of film and television for 66 years.

Winners at the Screen Actors Guild Awards

Film
Best ensemble cast: Birdman
Best actor: Eddie Redmayne, The Theory of Everything
Best actress: Julianne Moore, Still Alice
Best supporting actor: J.K. Simmons, Whiplash
Best supporting actress: Patricia Arquette, Boyhood

Television
Best ensemble cast, drama series: Downton Abbey (PBS)
Best ensemble cast, comedy series: Orange is the New Black (Netflix)
Best actor, drama series: Kevin Spacey, House of Cards (Netflix)
Best actress, drama series: Viola Davis, How to Get Away with Murder (ABC)
Best actor, comedy series: William H. Macy, Shameless (Showtime)
Best actress, comedy series: Uzo Aduba, Orange is the New Black
Best actor, TV film/miniseries: Mark Ruffalo, The Normal Heart (HBO)
Best actress, TV film/miniseries: Frances McDormand, Olive Kitteridge