The first of Thomas Søndergård's two Proms with the BBC National Orchestra of Wales placed Strauss alongside Mozart, his idol, and Nielsen, his very different near contemporary. It was, in some respects, an unwieldy evening. Fine conductor though he is, Søndergård is not a natural Straussian, and consequently this was a concert of two differing halves.

Søndergård seemed uneasy with the discursive form of Tod und Verklärung, with which he opened, shaping it tentatively at times and taking the difficult final peroration too slowly. Fits and starts replaced the music's natural ebb and flow. The drama, meanwhile, occasionally seemed mannered, and solemnity replaced ecstasy at the close. Strauss's dark, orchestral sound turned overly dense and a bit brass-heavy. Things brightened with the Burleske in D Minor for piano and orchestra. Søndergård responded more sharply to its form, a straightforward single movement sonata. It was low-key for a work that, as its title suggests, aspires to comedy, though Søndergård nicely emphasised the underlying Brahmsian influences that Strauss, turning towards Wagner, would later play down. The soloist was Francesco Piemontesi, who was hard-hitting and energetic, yet admirably witty, debonair and flamboyant.

Mozart was represented by his Rondo for Piano and Orchestra in A Major, K386 and Nielsen by his Fifth Symphony. Piemontesi is an exquisite Mozartean, elegant in style and fully aware of the emotional depths beneath the graceful surface. Nielsen's Fifth, meanwhile, completed in 1922, gazes at the "dissolution" (Nielsen's word) of Europe in the aftermath of conflict. Søndergård, at home in this music, was wonderfully alert to its anger, brutality and complex emotional seesawing between grief and optimistic defiance. The playing was committed and assured.

• Søndergård conducts the BBCNOW on 12 August at Royal Albert Hall. Box office: 0845 401 5034. The Proms continue until 13 September. Details: bbc.co.uk/proms.