American R&B superstars are not cut out to be self-effacing, Usher Raymond in particular: in an interview promoting his new album, Looking 4 Myself, he likens himself to Picasso. But perhaps he felt the tiniest jot of unworthiness when he glanced at the screen above the stage at this gig, which was globally live-streamed. Throughout the evening, it displayed live tweets from fans, who united in telling him that he's the greatest singer in history, and this one-off show was the best thing he has ever done. Typical was: "Sweat, baby, sweat! Appreciate every drop!"

A mortal might have blushed, but Usher has been in the R&B top tier for so long that little disturbs him. Admittedly, his confidence wasn't entirely misplaced: 18 years after his first album, the man is at the peak of his performing skills. Though flanked by the obligatory dancers and sci-fi graphics, his singing and dancing were authoritative, carrying even the most generic catalogue tracks. And he broke with tradition by keeping nearly all his clothes on throughout. If you blinked, you might have missed the coy flash of oiled pectorals.

As with his hero, Michael Jackson, the dancing is accorded as much prominence as the singing – leaping over a chair while moonwalking is standard – but for the onlooker, it was his gritty-sweet tenor that prevailed. Note-perfect versions of Yeah! – the hit that brought crunk to the mainstream – and the silly, party-rocking OMG were just great; so was the slow jam Burn, which was prefaced by an allusion to his recent divorce.

There were saggy moments, such as the groove-in-search-of-a-tune Bad Girl, and a plain weird one, in which electropopping new tracks Numb and Euphoria were played over the PA, while Usher stood and listened. But he gave every ounce of himself on the set-closing new single, Scream, knowing every drop of sweat was appreciated.