Anne Hathaway's jaw-dropping talk show moment

Anne Hathaway's Kelly Clarkson tribute show opening song. Photo / Supplied

Actress Anne Hathaway beat Kelly Clarkson at her own game this week, leaving the singer turned talk show host speechless and literally sweeping her off her feet.

Hathaway was visiting Clarkson's show to promote her new TV show WeCrashed, and stuck around to take part in the karaoke-esque game, Sing That Name That Tune.

The game sees former American Idol winner Clarkson – known for her incredible powerhouse vocals – go head-to-head with celeb guests as they try to recognise songs from their opening few notes and launch into passionate karaoke versions of them.

In a clip from the segment that quickly went viral, Clarkson's house band launched into an opening couple of notes that would be recognisable to any fans of her pop career.

But before Clarkson could clock what the song was, Hathaway was away – delivering a note-perfect rendition of Clarkson's biggest hit, 2004's Since U Been Gone.

Anne Hathaway's Kelly Clarkson tribute show opening song. Photo / Supplied

That sky-high chorus is not easy for just anyone to sing, but Hathaway nailed every note – and Clarkson dramatically collapsed before regaining her composure.

After a somewhat smug-looking Hathaway finished the chorus, Clarkson still couldn't believe she'd been trounced with her own biggest hit.

"How did you know it from just that?" Clarkson asked Hathaway. "She knew it from boom-boom-boom-boom-boom!"

"Kelly Clarkson, if you do not understand how much we all love that song – everybody here knew it!" Hathaway said, confessing it was one of her favourite songs.

"This is embarrassing," said a sheepish Clarkson.

Didn't know Anne Hathaway could sing? Are you new? Picture / AP

Among the many people sharing the clip online today, some have expressed their surprise that Hathaway can sing so well.

But other fans of the actor have been quick to point out that the star, who showed off her vocal chops in films like Ella Enchanted, even won an Oscar for her singing: She performed I Dreamed A Dream in the 2012 remake of Les Miserables (pictured above), picking up a Best Supporting Actress Oscar for her efforts.

Or, as another viral tweet put it today: "Anne Hathaway is a theatre kid; you will never beat a theatre kid at these types of games (even if you are the untouchable Kelly Clarkson)."