The Royal Court has been transformed into a boxing ring for Roy Williams’ new play, Sucker Punch. A new circle has been built to face to the old one, so we look down on the ring, and the punch bags, and the utilitarian chairs in the gym, where the old trainer Charlie (Nigel Lindsay) is putting the white welterweight hope (Jason Maza) through some punishing routines as we take our seats.

New corridors are plastered with cuttings of forgotten matches and champions. This amazing transformation by designer Miriam Buether comes at a price. The audience sections are alienated from each other. My recycled stalls leather seat was excruciatingly uncomfortable, jammed in at the end of a row. And the, in effect, awkward traverse staging and over-microphoned actors (why?) make a jumble of much of the text.

Most crucially, you miss almost all of the main man Leon’s terrific spotlight speeches about his early fights, full of detail and colour, in a sort of “big night” blare. Content is sacrificed to atmosphere, which is nonetheless terrific; especially in the climactic slow motion showdown between Leon (an absolutely brilliant, slyly athletic and skipping Daniel Kaluuya) and his best friend Troy (pin-sharp Anthony Welsh).

These boys are black, climbing out of the ghetto into the ring, rather like the heroes of two great American boxing plays, Clifford OdetsGolden Boy and Howard Sackler’s The Great White Hope. Williams aims lower than either of those writers, but he lands some telling blows about racism in the early 1980s, Mrs Thatcher (surprise, surprise) and a few jabs about the incipient riots in Brixton and Tottenham.

Mostly though, and very skilfully, Williams shuffles his six main characters to show how the lads graduate from cleaning toilets to fighting each other, playing around with the trainer’s daughter (sparkish Sarah Ridgeway), and dealing with parental expectation (Trevor Laird is a delight as Leon’s devious dad), while Charlie’s gym goes down the shoot and the big bucks beckon in the momentous, fur-coated shape of Gary Beadle’s American manager.

It’s all good fun and should be a riot if it finds its right audience. I just wish Sacha Wares’ dynamic production – with exciting lighting by Peter Mumford and great boxing choreography by Leon Baugh – was as thoroughly audible as it is enjoyably authentic and spirited.