The first piano piece remaining in the catalog of works. Composed for Hiroaki Ooi, it was premiered in December 1992 at Yamamura Salon in Ashiya and dedicated to him. It was partially revised in 1997. At the time of its composition, the composer was attempting to write pieces by systematically reordering and arranging the sequence of various elements constituting music (such as pitch, note value, or characteristic blocks). The title TROS is also the word "sort" spelled backward. In this TROS III, not only pitches and note values but also characteristic blocks are juxtaposed, with their order reordered, sometimes clashing within the same register.