"American Hustle" cast

The jubiliant stars of David O. Russell’s “American Hustle” take to the stage to accept the cast award, a significant recognition in the lead-up to the Oscars. (Robert Gauthier / Los Angeles Times / January 18, 2014)

 "American Hustle" won just a single trophy at the Screen Actors Guild Awards — the really important one.

The cast of David O. Russell's con-man tale took home SAG's cast award Saturday night, nudging "American Hustle" ahead of Oscar season's months-long front-runner, "12 Years a Slave," in what is proving to be a tight race.

After collecting 10 Oscar nominations Thursday, "American Hustle" also beat out the casts of "August: Osage County," "Dallas Buyers Club" and "Lee Daniels' The Butler" for the SAG Award.

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The SAG category of cast in a motion picture is often seen as a reliable predictor for the Academy Award best picture prize because many SAG members are part of the actors branch of the Academy of Motion Picture Arts and Sciences, the largest voting bloc in the organization.

It's perhaps not surprising that the actors' union rewarded a movie with a large cast of A-listers delivering their winningest screwball performances. A drama set in the 1970s and early '80s, "American Hustle" stars Christian Bale and Amy Adams as con artists forced by an FBI agent (Bradley Cooper) to participate in an elaborate sting to catch corrupt politicians. Jennifer Lawrence plays Bale's character's unpredictable wife.

"David O. Russell makes you feel like part of a family," Cooper said, accepting "American Hustle's" award on stage at the Shrine Exposition Center in Los Angeles. "He's an actor's director."

On the television side of things, AMC's "Breaking Bad" won for performance by an ensemble in a drama series and ABC's "Modern Family" was named the top ensemble in a comedy for the fourth consecutive year. Bryan Cranston, Maggie Smith, Ty Burrell and Julia Louis-Dreyfus all won individual actor statuettes as well.

SAG Awards 2014: Quotes | Highlights | Photo booth

In the individual film acting categories, SAG largely rewarded this Oscar season's favorites.

Matthew McConaughey, who already won a Golden Globe and Critics Choice Award in the past week, won the lead actor prize for his performance as homophobic but ultimately pioneering AIDS patient Ron Woodroof in the drama "Dallas Buyers Club."

Accepting the award, McConaughey gave a passionate if somewhat rambling speech in which he mentioned Neptune, bull rides and playing characters who are, "feverishly drunk on their obsessions."

"I've been having fun with the circus," McConaughey told reporters backstage, explaining his loopy behavior. "If I wasn't having fun, take me behind the woodshed and straighten me out."

Lead female actor winner Cate Blanchett kind of did. When a teleprompter warned her she was running out of time just seconds into her acceptance speech for her performance in "Blue Jasmine," Blanchett said, "Matthew McConaughey spoke about Neptune. I think I can have five seconds."

Lupita Nyong'o took home her first SAG Award on Saturday, after winning a supporting trophy for her performance as a brutally abused slave in "12 Years a Slave." In her speech, Nyong'o thanked Solomon Northup, whose 19th century memoir inspired the film.

"Thank you for taking a flashlight and shining it underneath the floorboards of this nation and reminding us what we stand on," Nyong'o said.

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Jared Leto also spoke on a serious note after winning the supporting actor prize for "Dallas Buyers Club," in which he plays Rayon, a transgender woman with AIDS.

"I'd like to dedicate this special honor to people who have lost their lives to this dreadful disease ... the Rayons of the world," he said.

The guild gave its Life Achievement Award to Rita Moreno, the Puerto Rico-born actress, dancer and singer best known for playing the role of Anita in "West Side Story." At 82, Moreno made one of the more vital appearances of the evening, dropping an F-bomb and singing "This is All I Ask" in a leg-baring dress.