Washington, Sept 2 : Rocker Pete Wentz was reportedly left red-faced when his trousers fell down onstage – exposing his blue patterned underpants.

The ‘Fall Out Boy’ bassist was performing with his group at the Leeds music festival in England when the humiliating ''wardrobe malfunction'' occurred.

In the meantime, one of the production assistants dashed to save the rocker''s blushes.

"Pete was so busy singing he didn''t notice his trousers had slipped down, but thankfully one his roadies stepped in and pulled them up to avoid any further embarrassment," Contactmusic quoted a source as saying. (ANI)