| ITF M25 Takasaki | 2023/09/17 01:00 | Ryotaro Matsumura v Seiya Nakanishi | 6-2,6-4 |
| ITF M15 Tsukuba | 2024/03/30 02:00 | Ryotaro Matsumura v Kokoro Isomura | 1-6,6-7 |
| ITF M15 Tsukuba | 2024/03/29 06:15 | Ryotaro Matsumura v Sanhui Shin | 7-6,6-7,7-6 |
| ITF M15 Tsukuba | 2024/03/27 05:30 | Vit Kalina v Ryotaro Matsumura | 6-3,0-6,2-6 |
| ITF M15 Tsukuba | 2024/03/25 07:30 | Ryotaro Matsumura v Jumpei Yamasaki | 7-5,7-6 |
| ITF M15 Tsukuba | 2024/03/24 01:00 | Yeongseok Jeong v Ryotaro Matsumura | 3-6,4-6 |
| ITF M15 Nishi-Tokyo | 2024/03/19 01:00 | Leo Vithoontien v Ryotaro Matsumura | 3-6,6-4,10-6 |
| ITF M15 Hinode | 2024/03/11 05:40 | Ryotaro Matsumura v Gen Nakamura | 3-6,5-7 |
| ITF M15 Hinode | 2024/03/11 01:00 | Ryotaro Matsumura v Mao Takada | 6-2,6-0 |
| ITF M15 Hinode | 2024/03/11 04:45 | Seiya Nakanishi v Shunsuke Nakagawa | 4-6,2-6 |
| ITF M15 Hinode | 2024/03/11 01:00 | Jumpei Yamasaki v Seiya Nakanishi | 5-7,6-4,8-10 |
| ITF M15 Yanagawa | 2023/12/25 00:30 | Kazuma Kawachi v Seiya Nakanishi | 6-3,6-0 |
| ITF M25 Takasaki | 2023/09/17 01:00 | Ryotaro Matsumura v Seiya Nakanishi | 6-2,6-4 |
| ITF M25 Sapporo | 2023/09/05 04:15 | Issei Okamura v Seiya Nakanishi | 6-1,6-1 |
| ITF M25 Sapporo | 2023/09/04 03:35 | Ryusuke Horiuchi v Seiya Nakanishi | 6-4,2-6,10-12 |
| ITF M15 Karuizawa | 2023/05/28 01:15 | Seiya Nakanishi v Yua Taka | 4-6,2-6 |
| ITF M25 Kashiwa | 2023/04/02 00:30 | Jeremy Jin v Seiya Nakanishi | 6-3,6-2 |