You don't expect the show to be stolen by a cello sonata.

But that's exactly what happened at Monday's concert in the Summer Festival of the Seattle Chamber Music Society. Efe Baltacigil, who has just finished his first season as the Seattle Symphony's principal cellist, made the strongest impression of the evening in the mercurial Debussy Cello Sonata, in the midst of the longer, louder works on the program.

With the pianist Adam Neiman, Baltacigil poured out luscious, elegant tone, perfectly controlled harmonics, and stylish phrasing — all with a sense of evident enjoyment. This is a cellist of superb nuances and spontaneous musicality, and Neiman partnered him beautifully.

But Seattle Symphony fans in the audience may have felt that sinking feeling as they read the line in Baltacigil's bio about next season's engagement with the Berlin Philharmonic and Sir Simon Rattle. Enjoy his Seattle playing while you can.

Monday's program opened with Frank Bridge's picturesque "Phantasy for Piano and Strings in F-Sharp Minor," in which the excellent violinist Stefan Jackiw was first among equals in a rhapsodic interpretation of this pretty but insubstantial trifle. (The ensemble included violist Cynthia Phelps, cellist Robert deMaine, and pianist Jeremy Denk.)

Dvorak's "Cypresses for String Quartet" appeared for the first time on any of the festival's programs; these modest little pieces have sweet melodies and were surprisingly effective in the hands of four top players. Violinist Augustin Hadelich, who drew sustained cheers in his festival performances this past Friday, did wonders with the melodic lines, supported by violinist Amy Schwartz Moretti, violist Richard O'Neill and cellist Ronald Thomas.

The evening's finale, the mighty Rachmaninoff Symphonic Dances for Two Pianos (Op. 45), continued the festival's emphasis on two-keyboard instrumentation. Energetic, propulsive, and occasionally motoric, this three-movement work requires two genuine virtuosi, which we had in Orion Weiss and Inon Barnatan.

There are wonderful, exciting passages strung together by a lot of uninspired development sections that sound as if Rachmaninoff were marking time and filling space. Still, the performance was exciting enough to banish reservations about the work's musical merits amid that virtuoso cascade of notes.

Melinda Bargreen also reviews concerts for 98.1 Classical KING FM. She can be reached at mbargreen@aol.com.