Oscar is a trip for Jennifer Lawrence

(AP) - Jennifer Lawrence's performance in "Silver Linings Playbook" was flawless enough to capture the best actress Oscar. She wasn't so adroit in claiming the trophy.

Lawrence stumbled as she took the steps to the Oscar stage, falling to her knees in her flowing Dior gown. That drew a sympathetic ovation from the auditorium.

She remained endearingly flustered during her acceptance speech, thanking her family, those who worked with her on the film and wishing a "Happy Birthday" to a fellow nominee, Emmanuelle Riva of "Amour," who turned 86.

"What do you mean what happened?

"Look at this dress. I tried to walk up stairs in this dress," she said of her white, floor-length gown. "I think I stepped on the fabric and they wax the stairs."

She thought of a "bad word" to say when she tumbled, Lawrence said, but kept it to herself.

She had already been bleeped by ABC when she let loose with a four-letter word while joking with Kristin Chenoweth on the red carpet.

Asked how she got ready for the day, Lawrence said it was "chaotic" from the start, with her family taking over the house to prepare for the big evening.

After fumbling for a more descriptive answer, she apologized: "I'm sorry. I did a shot."