A minor, 4/4 time. In sonata-allegro form.

The powerful first theme is primarily characterized by a descending motif in parallel thirds and an accompaniment of dynamic leaps. The sharp rhythms and dissonances formed by tritones in the bass leave a vivid impression. In addition to the sonorities, the asymmetrical phrase structure further enhances the instability. The transition section gradually releases energy and moves to the second theme. In complete contrast to the first theme, a simple melody, almost fragile in character, is presented in octave unison.

The extensive development section is contrapuntally constructed. The beginning primarily features the opening three notes of the second theme (the C-D-F motif), but the articulation and dynamics are completely transformed, and the former lyrical atmosphere is entirely absent. From the middle section onwards, along with fragmentary motifs of parallel thirds from the opening theme, a subsidiary theme appears in its complete form, sometimes augmented, forming the climax of the piece. From this point, a motif based on the latter half of the second theme, primarily consisting of a descending figuration in triplets, is emphasized.

As if disproportionate to the scale of the development section, the recapitulation of the themes is extremely condensed. After the first theme, the second theme appears in its augmented form from the development section, and, interspersed with elements that appeared in the recapitulation, the opening motif appears alone, making a statement, concluding the movement.