Pop superstar Britney Spears suffered an embarrassing wardrobe malfunction on Saturday (28Dec13) after her costume became unzipped while performing during her new Las Vegas residency.

The Toxic hitmaker was in the middle of her song Circus when the back of her dress opened up and nearly slipped off.

However, Spears remained ever the professional and continued to strut her stuff onstage as a back-up dancer came to her rescue and secured the zipper.

The singer kicked off her two-year residency, Britney: Piece Of Me, on Friday (27Dec13) in front of a star-studded crowd, including Katy Perry, Selena Gomez and Miley Cyrus.