LOS ANGELES Melissa Leo won her first Academy Award on Sunday for her supporting role in "The Fighter," a movie that propelled the 50-year-old actress into the mainstream for the first time in her career.
Leo was considered a favorite for the prize, but faced strong competition from both co-star Amy Adams and Helena Bonham-Carter for "The King's Speech." All played real-life characters.
But Leo seemed overwhelmed when she stepped up to receive her Oscar and let a rare "F-word" slip out on the movie industry's biggest night.
"Will you pinch me?", she asked presenter Kirk Douglas.
"Oh my god! Oh wow!. Really, really, really truly wow. I know there have been a lot of people saying some real, real nice things to me for several months now. But I am just shaking in my boots here," she said.
Leo starred in "The Fighter" as Alice Ward, the feisty mother of two New England boxing heroes played by Mark Wahlberg and Christian Bale, who picked up the best supporting actor award later in the show.
While her characterization of the brassy matriarch was not exactly sympathetic, Leo has gone out of her way during awards season to paint Ward as an unsung heroine with a good heart.
Leo got the first language "bleep" of the awards show telecast, while thanking the members of the Ward family on whose story "The Fighter" was based.
She later apologized backstage for using the "F-word" -- a rare incident at the live ceremony for the movie industry's highest honors.
"I apologize to anyone they offend. There is a great deal of the English language that is in my vernacular. I did not mean to offend, and (it was) a very inappropriate place to use that particular word," Leo told journalists.
Leo was nominated for an Oscar two years ago for her lead role in "Frozen River," an arthouse drama that grossed just $2.5 million at the North American box office. "The Fighter," by contrast, has earned about $88 million to date.
Leo thanked the members of the Academy of Motion Picture Arts and Sciences who had voted for her, adding that the Oscars are about "selling motion pictures and respecting the work."
The other supporting actress nominees were Hailee Steinfeld for "True Grit" and Jacki Weaver for "Animal Kingdom."