Rihanna To Be X Factor Judge

The 'Cheers' singer will have a key role on the UK show.

Rihanna has reportedly been lined up to perform for contestants during the boot camp phase.

After her performance though, the wannabe singers will have to sing for and be judged by the star.

"[It will be] very nerve-racking for the contestants but great viewing for the audience," a source told the Daily Star.

"Who could follow Rihanna and be confident? This will definitely weed out the good from the bad."

The series is set to start later this month, with Rihanna due in the UK for her 'Loud' tour in September.