The piece is written in a relatively free form, to the extent that it seems inappropriate to categorize it within a specific formal structure. In the first half, the main theme from the beginning of the movement appears a total of four times, with both the piano and violin serving as melodic voices. After an intervening musical idea, the original melody is varied from the third presentation of the theme by the piano. Furthermore, when the violin varies the theme, it begins with a modulation to B-flat minor and gradually moves away from the theme. Modulations continue using enharmonic equivalents, and upon finally returning to the tonic key of B-flat major, a sixteenth-note motive derived from the first measure of the opening theme melody is repeated. At the end of the movement, after the middle section where harmonies continuously shift, the dominant and tonic chords of the home key are repeated, as if to emphasize the tonic.

From an instrumentation perspective, it is evident how crucial the violin part functions, not only because the music is formed by the violin playing the melody alternately with the piano or through exchanges of short motives resembling a “dialogue” between the two instruments, but also from the fact that the violin becomes the principal voice during the significant modulation to the minor key in the middle section.