Catriona Stewart's verdict: three stars

The sun, for modesty, has removed his hat and is using it to shield his eyes. On the Radio One stage Kesha, the American rowdy-pop siren, is firmly establishing her status as bringer of party.

Backed by a brace of glitter-sprayed, tight-pants-wearing beefcakes, Kesha is baring nearly all in a high-cut, sequin leotard. What she lacks in grace she makes up for in sheer, brazen, energetic raunch.

Sex is high on her agenda - that between any gender - and much of her stage chat is entirely unsuitable for printing. I can only express relief that the audience failed to go along with her bawdier suggestions.

"Live every day and every night like you're going to die young," she hollers, the organisers looking anxiously towards the anti-drugs posters dotted around the site, before thudding into the song Die Young.

She whips through hits and high-energy dance routines in a frenzy, pausing only to down a can of Tennent's.

Rock tune Dirty Love leads to an unprintable monologue about her personal preferences, as does Blah Blah Blah, during which men in eyeball costumes dance around her. Later, the men are in glamorous drag.

Visually, she's a treat; at one point she drives on in a miniature Volkswagon Beetle painted in the Gay Pride flag.

She launches beach balls and streamers at the crowd and has giant legs and a huge pig inflated on the stage. Don't Stop is a highly-anticipated, highly-enjoyable closer.

For a showing pushing so much sex, Kesha is oddly unsexy. But she is ballsy, slick and a great deal of fun.