Stadium: Court 3 Round: 54 Ground: Hardcourt outdoor
| ITF M25 Kashiwa | 2023/04/02 02:30 | Koki Matsuda v Krittin Koaykul | 6-3,6-3 |
| ITF M25 Tsukuba | 2023/03/29 00:30 | Koki Matsuda v Ryotaro Taguchi | 6-3,2-6,2-6 |
| ITF M25 Tsukuba | 2023/03/27 04:00 | Koki Matsuda v Asahi Harazaki | 7-6,6-7,10-8 |
| ITF M25 Tsukuba | 2023/03/27 00:30 | Koki Matsuda v Taki Adachi | 6-3,6-1 |
| UTR Pro Tennis Series Miki | 2022/12/10 03:57 | Koki Matsuda v Kazuki Nishiwaki | 3-6,0-0 |
| UTR Pro Tennis Series Miki | 2022/12/08 00:30 | Kento Tagashira v Koki Matsuda | 4-6,4-6 |
| UTR Pro Tennis Series Miki | 2022/12/05 02:00 | Ying-Ze Chen v Koki Matsuda | 2-6,2-5 |
| Challenger Yokkaichi | 2022/11/21 01:00 | Colin Sinclair v Koki Matsuda | 6-3,6-4 |
| ITF M25 Kashiwa | 2023/04/02 00:30 | Taketo Takamisawa v Issei Okamura | 1-6,2-6 |
| ITF M25 Tsukuba | 2023/03/27 05:00 | Ryotaro Taguchi v Issei Okamura | 7-5,6-2 |
| ITF M25 Tsukuba | 2023/03/27 00:30 | Seiya Nakanishi v Issei Okamura | 2-6,4-6 |
| ITF M15 Aktobe | 2023/03/06 09:40 | Issei Okamura v Mykhailo Mossur | 4-6,6-3,5-10 |
| ITF M15 Aktobe | 2023/02/28 07:30 | Issei Okamura v Max Batyutenko | 6-7,6-4,7-10 |
| ITF M15 Aktobe | 2023/02/27 10:55 | Issei Okamura v Alexander Orlov | 6-2,7-6 |
| ITF M25 Burnie | 2023/02/07 23:00 | Adam Walton v Issei Okamura | 6-3,6-4 |
| ITF M25 Burnie | 2023/02/06 00:00 | Issei Okamura v Stefan Vujic | 7-6,7-6 |