It is not hard to understand Solange Knowles' reluctance to use her surname for professional purposes. This fledgling diva spent the first part of her career in the shadow of her sister Beyoncé, including spells working as a backing dancer for Destiny's Child and playing support slots to her big sis on solo tours.

Solange's debut album, Solo Star, released in 2003 when she was just 16, was a forgettable exercise in generic R&B, but its recent follow-up, Sol-Angel and the Hadley St Dreams, is far more spectacular. Its lopsided, fascinating fusion of clever Motown appropriations and psychedelic soul hints she could prove a more maverick talent than her elder sibling.

Beyoncé gazes down on tonight's show from an above-stage balcony, but Solange's effervescent set soon wrests away the crowd's attention. Flanked by two Martha and the Vandellas-like micro-skirted backing singers and a tight Stax revue-style band, she is a spiky focus in her idiosyncratic outfit of Mickey Mouse T-shirt, gold lamé ra-ra skirt and killer heels.

Her songs have the Motown knack of cutting straight to the pained heart of failing relationships, and she is happy to share their personal origins. "This was written for my ex's side-chick," she divulges, dripping honeyed scorn, before Would've Been the One, a soulful essay of cathartic rage driven by Supremes-like handclaps. She dedicates the funky 6 O'Clock Blues to Barack Obama, then, after orchestrating chants of "Yes we can!", abandons the stage to perform the closing I Decided while wigging out in the midst of an infatuated dance floor. The crowd have long forgotten there is even another Knowles in the house.