Emma Watson played down her panty-flashing wardrobe malfunction Wednesday, insisting it could have been a lot worse.

The 19-year-old actress showed off more than she'd intended when her dress parted at the London premiere of "Harry Potter and the Half-Blood Prince" on Tuesday.

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But when television host David Letterman pointed out the faux-pas on "The Late Show," a blushing Emma replied: "This was a small wardrobe malfunction that happens.

"At least I'm wearing underwear," the 19-year-old star added, before hanging her head in her hands to say she's "still learning" this stuff.

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