Paul Lewis's traversal of all five of Beethoven's piano concertos during the Proms season – apparently the first by a single artist – began with a double dose: the First and Fourth Concertos, with the BBC Symphony and conductor Jirí Belohlávek supplying the orchestral forces, as they did on a recent recording of the complete set.

As it turned out, the combination did not gel on this occasion until the second of the two. The First Concerto, in which Beethoven imbues the Mozartian model with distinctive touches of his own, needed more character, humour and flow. Nevertheless, Lewis's fingerwork was immaculate and Belohlávek's accompanying as well defined as the orchestra's tone was warm.

The more intimate and uniquely individual Fourth Concerto was on another level. There was total unanimity of purpose and gesture between conductor and soloist, and the subtle, varied character of Beethoven's inimitable ideas was presented with absolute authority. Interestingly, the second half began with a neat and spirited account of the Prometheus overture, whereas the Egmont overture, which opened the concert, was no more than respectable, with some unfortunate woodwind mishaps.

The evening turned out to be a special one for piano fans. The Portuguese pianist Maria João Pires made a rare appearance with a generous selection of Chopin's nocturnes as the late-night event. Received wisdom suggests the Albert Hall is too big for such music, but in this case the sonic unpredictability of the venue conspired with the pianist herself to refute it.

Pires's playing was unostentatious but commanding, controlled yet free-flying in its sensitivity to the fluidity of Chopin's lines, and in its responsiveness to the scope of pieces still sometimes marked down as delicate miniatures.