Head-to-Head
Overview
Hiromasa Koyama and Luca Castelnuovo have met 1 time so far, all in 2026. Luca Castelnuovo leads 1–0. Their first encounter was at the 2026 M25 Taipei 2 (R16), won by Luca Castelnuovo.
By surface
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Hiromasa Koyama and Luca Castelnuovo have met 1 time so far, all in 2026. Luca Castelnuovo leads 1–0. Their first encounter was at the 2026 M25 Taipei 2 (R16), won by Luca Castelnuovo.