British actress Keira Knightley calls her rejection by makers of "The Phantom of the Opera" the "singularly most embarrassing experience of my entire life".

The "Bend It Like Beckham" star had auditioned for the lead female role in the opera blockbuster, only to be told by the casting directors that she simply couldn't sing, reports Ireland Online.

The 20-year-old says she was relieved when they offered the role of Christine to trained soprano Emmy Rossum.

"I absolutely knew I couldn't sing it. But I went in, and they were like: 'No, no, anybody can sing. Just try it out.' And I sang and the guy went, 'You really can't sing, can you'," Knightley was quoted as saying.