Avril Lavigne

Pop-punk rocker Avril Lavigne will sit behind the judges' table during American Idol's Season 9 audition tour.

See photos of Lavigne

Lavigne will join Simon Cowell, Randy Jackson, and Kara DioGuardi at the Los Angeles auditions later this week, Fox announced. Lavigne will judge the first day of auditions; the second will be handled by Katy Perry, whose appearance was previously announced but never scheduled.

Check out photos of the Idol judges

Lavigne and Perry join a growing list of celebrity judges that also includes Victoria Beckham, Mary J. Blige, Joe Jonas, Neil Patrick Harris, and Kristin Chenoweth.