A bare-faced Fergie failed to hide her make up-free mug as she stepped out for a day at the studio in Burbank, California.

Dressed down in black sweat pants and wearing some slippers, the Fergalicious star clearly wasn't ready for her close-up as she attempted to hide under a pair of shades and a baseball cap.

Fergie - who is the face of Mac VIVA Glam - looked a world away from her normally groomed self, sporting a shiny complexion and puffy cheeks.

The star was getting ready to shoot her new music video.

It just shows that a good hair and make-up team can work wonders!

See more stars caught without their slap below