Kirill Gerstein, Queen Elizabeth Hall, London

Pianist Kirill Gerstein (Getty Images)

One lesson to be drawn from Keith Jarrett’s recent Southbank recital was how porous the border now is between jazz piano and its classical counterpart.

This was partly to do with his keyboard technique, and partly with the way his improvisations clearly strove to mirror the written-out music of Gyorgy Ligeti. But though increasing numbers of classical pianists now flourish a jazz alter ego, they tend to reserve it for encores - as though it’s not quite kosher, and doesn’t deserve a place in the programme proper.

Kirill Gerstein is one of the few pianists to have tackled this question head on, and he opened his Southbank recital with the UK premiere of a piece he had commissioned from the jazz composer Brad Mehldau. In his programme-note, Mehldau made it clear that he wanted to associate his ‘Variations on a Melancholy Theme’ with Bach’s Goldbergs and Beethoven’s Diabellis, and though that comparison was frankly stretching it, his work did follow a similar form.

Gershwin was the comparison which initially came to mind, as the free-flowing melody was given gentle swing and a harmonic coloration to match. Sometimes it felt like a Jarrett-type improvisation, other times you could see why Gerstein was keeping such a close eye on his natty little pedal-operated Kindle, as the chords were heaped ever higher. The programme had promised a piece lasting 12 minutes, but it turned out to be half an hour: an interesting technical exercise, but not remotely in the same league as the works which followed.

The first of these was Brahms’s titanic ‘Variations on a Theme by Paganini’, for which Gerstein switched on the high-octane virtuosity for which he is famed. In the first few variations his touch was velvet-pawed, but this was simply a pacing of his performance before building on Brahms’s mighty lyricism and muscular dissonances until the edifice acquired epic grandeur.

Haydn’s exquisite ‘Variations in F minor’, which followed after the interval, allowed him to deploy completely different talents as he allowed the Baroque ornamentation of the parallel themes to blossom gracefully. Finally the circus came to town with the jugglers, tumblers, and commedia dell’arte figures of Schumann’s ‘Carnaval’. Here every episode was vividly characterised, and every phrase freshly imagined; the Rachmaninov encore rounded things off perfectly. With this 34-year-old Russian-American conservatoire professor and his ilk now setting the pace, the pianistic future looks positively rosy.