Nicola Benedetti, Royal Festival Hall, London

There has been a lot of hype about the violinist Nicola Benedetti since she won the BBC Young Musician of the Year competition in 2004. This was the 17-year-old's RFH debut in as bizarre a set of circumstances as any tall story might suggest.

A lovelorn businessman had coughed up £100,000 for his beloved - named on the programme as Heather - to hear her favourite tune played by the cash-strapped Royal Philharmonic Orchestra, plus a few extra brass. Janacek's Sinfonietta duly began the programme, said brass ranged across the back like a military guard. This highly original piece implies smallness but in fact involves full orchestra, and is mighty difficult to boot. David Murphy, conducting, did not offer confidence: he achieved brash brass but not lush strings, and far from impeccable ensemble and intonation.

Then came Benedetti, not only to perform but to make her first "album" fly. Record companies are pretty desperate these days; classical sales have plummeted, technology permits virtual theft, so the young, talented and winsome are obvious targets. Post-prize, Deutsche Grammophon hastily signed Benedetti for a reputed £1m. This was the concert of the disc, although her winning work - Szymanowski's First Violin Concerto - wasn't included.

Chausson's Poème was recorded by Menuhin at Benedetti's age. She's not a Menuhin but she does have a freshness and innocence that makes this work a good choice. Her solo opening, with no orchestral backing, was beautifully controlled. Technically, she's awesome - something that competitions can judge too easily - but she's very musical, too, her phrasing long and intelligent, and she's not afraid to use portamenti. Her lovely singing sound was both well-focused and yearning. The orchestra responded sensitively but Murphy seemed unmoved.

Fragment for the Virgin, written by Sir John Tavener for Benedetti, has, since its Wigmore Hall premiere earlier this year, been re-cast for soloist and strings. In its astonishingly brief four and a half minutes, Benedetti demonstrated an intense sound, with wide-vibrato and appropriate "Eastern-style" portamenti for this slow, stately piece, written "to the Virgin, not only as Mother of Christ but Mother of the Cosmos". Sir John's instructions are that the music should be played "at the breaking point of intensity, whether it be fiercely and piercingly loud or infinitely soft". Murphy garnered no such effects from his band.

Saint-Saëns's Havanaise is a technical show-stopper and Benedetti showed she'd got it - impeccable harmonics, fantastic double-stops and incredible confidence high up. But I began to wonder at the size of her sound, the range of her colours, and the degree of characterisation on offer. Only time (and a better conductor) will tell.

Nicola Benedetti performs Mozart at the Mostly Mozart festival, Barbican, London EC2 (0845 120 7500) 30 July