Stadium: Court 3 Round: 54 Ground: Hardcourt outdoor
| ITF M25 Sapporo | 2023/09/10 03:00 | Ryotaro Matsumura v Yuta Tomida | 6-3,6-7,9-11 |
| ITF M25 Sapporo | 2023/09/08 01:00 | Sora Fukuda v Ryotaro Matsumura | 4-6,6-3,6-4 |
| ITF M25 Sapporo | 2023/09/07 03:00 | Ryotaro Matsumura v Tatsuma Ito | 7-6,6-4 |
| UTR Pro Noda | 2023/08/26 04:45 | Naoya Honda v Ryotaro Matsumura | 6-2,6-1 |
| UTR Pro Noda | 2023/08/25 05:20 | Ryotaro Matsumura v Paul Howe | 6-2,6-0 |
| UTR Pro Noda | 2023/08/23 02:15 | Ryotaro Matsumura v Tomonobu Inagi | 6-0,6-2 |
| UTR Pro Noda | 2023/08/22 04:10 | Ryotaro Matsumura v Brody Nejedly-Krall | 6-1,6-4 |
| UTR Pro Noda | 2023/08/21 03:30 | Marsel Znuderl v Ryotaro Matsumura | 0-6,0-6 |
| 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 |
| ITF M25 Tsukuba | 2023/03/27 00:30 | Seiya Nakanishi v Issei Okamura | 2-6,4-6 |
| Challenger Yokohama | 2022/10/30 02:35 | Seiya Nakanishi v Daisuke Sumizawa | 3-6,0-6 |
| ITF M25 Sapporo | 2022/09/01 02:50 | Rio Noguchi v Seiya Nakanishi | 6-0,6-3 |