G major, 3/4 time.

Instead of the typical sonata form for a first movement, a form akin to rondo-sonata is employed.

The main theme presented at the beginning is an energetic yet somewhat off-key fanfare. The piano part spans a wide range, dominating the space. The harmonic progression is based on triads with roots ascending by a fourth (G→C→F→B), resulting in a relatively simple sound. However, the simplicity of the sound emphasizes the thrilling interplay between the solo piano and the orchestra. This theme is sustained for a long duration, interspersed with various musical ideas.

The episodes appearing between the themes are each brief; just as one might momentarily immerse themselves in sweet lyricism, they are immediately drawn back to the energetic theme, and even when rhythms primarily based on triplets emerge, they are assimilated back into the dotted rhythm of the fanfare.

In the section corresponding to the development, fragments of the theme and episodes appear one after another, ultimately leading the listener to a climax at the return of the theme in the recapitulation. Subsequently, the movement concludes with a very brief coda, while firmly retaining the fanfare elements.