Swalla Jason Derulo feat. Nicki Minaj & Ty Doll Download 'Swalla' on iTunes
The 'Price Tag' singer challenged a Jessie J lookalike to a dance off during her opening performance at the 2011 MOBO Awards!
Jessie J began her performance in her usual onstage throne and wearing a trilby hat.
Midway through her performance of 'Do It Like A Dude' Jessie J was joined onstage by a mock Jessie J and the pair proceeded to have a dance off.
Meanwhile two of Jessie's amazing backing dancers left the stage and went into the auditorium wearing head cameras.