Stadium: Court 4 Round: 25 Ground: Hardcourt outdoor
| ITF M15 Nakhon Si Thammarat | 2023/06/07 03:30 | Daisuke Sumizawa v Maximus Jones | 1-6,2-6 |
| ITF M15 Karuizawa | 2023/06/01 00:30 | Sora Fukuda v Daisuke Sumizawa | 6-3,6-4 |
| ITF M15 Karuizawa | 2023/05/30 07:35 | Taketo Takamisawa v Daisuke Sumizawa | 2-6,4-6 |
| Challenger Busan | 2023/05/08 02:00 | Daisuke Sumizawa v Woobin Shin | 6-2,3-6,2-6 |
| Challenger Gwangju | 2023/04/30 04:10 | Daniel Masur v Daisuke Sumizawa | 6-0,6-4 |
| ITF M25 Kashiwa | 2023/04/06 01:30 | Daisuke Sumizawa v Yunseong Chung | 2-6,2-6 |
| ITF M25 Kashiwa | 2023/04/05 03:15 | Ryotaro Taguchi v Daisuke Sumizawa | 6-7,7-6,6-7 |
| ITF M25 Tsukuba | 2023/03/30 02:50 | Hiroki Moriya v Daisuke Sumizawa | 7-5,6-1 |
| ITF M15 Brcko | 2023/05/22 07:30 | Taiyo Yamanaka v Timothy Gray | 6-4,6-4 |
| ITF M15 Prijedor | 2023/05/18 08:45 | Igor Gimenez v Taiyo Yamanaka | 6-4,4-6,10-5 |
| ITF M15 Doboj | 2023/05/10 14:30 | Marat Sharipov v Taiyo Yamanaka | 6-3,6-2 |
| ITF M15 Doboj | 2023/05/09 08:00 | Taiyo Yamanaka v Radomir Tomic | 2-6,6-7 |
| ITF M15 Doboj | 2023/05/08 08:00 | Taiyo Yamanaka v Federico Mirgone | 6-0,6-0 |
| ITF M25 Kashiwa | 2023/04/03 01:00 | Renta Tokuda v Taiyo Yamanaka | 6-0,7-5 |
| ITF M25 Kashiwa | 2023/04/02 00:30 | Ko Suzuki v Taiyo Yamanaka | 1-6,6-3,11-13 |
| ITF M25 Tsukuba | 2023/03/27 00:30 | Taiyo Yamanaka v Naoki Tajima | 6-4,5-7,8-10 |