Stadium: Court 9 Round: 26 Ground: Hardcourt outdoor
| ITF M25 Sapporo | 2022/08/30 02:55 | Keisuke Saitoh v Daisuke Sumizawa | 5-7,6-3,4-6 |
| ITF M15 Sharm El Sheikh | 2021/02/16 09:25 | Daisuke Sumizawa v Keisuke Saitoh | 2-6,4-6 |
| ITF M25 Cairns | 2023/10/12 00:00 | Omar Jasika v Daisuke Sumizawa | 6-1,6-2 |
| ITF M25 Cairns | 2023/10/10 23:50 | Daisuke Sumizawa v Taiyo Yamanaka | 6-2,6-2 |
| ITF M25 Cairns | 2023/10/06 02:25 | Daisuke Sumizawa v Ajeet Rai | 6-4,5-7,2-6 |
| ITF M25 Cairns | 2023/10/05 02:45 | Daisuke Sumizawa v Kody Pearson | 6-2,1-6,6-4 |
| ITF M25 Cairns | 2023/10/04 03:15 | Daisuke Sumizawa v Corban Crowther | 7-6,4-6,6-1 |
| ITF M25 Takasaki | 2023/09/21 03:15 | Naoki Nakagawa v Daisuke Sumizawa | 7-5,6-4 |
| ITF M25 Sapporo | 2023/09/15 00:55 | Koki Matsuda v Daisuke Sumizawa | 6-0,7-6 |
| ITF M25 Sapporo | 2023/09/13 01:00 | Daisuke Sumizawa v Yunseok Jang | 6-3,6-4 |
| ITF M25 Takasaki | 2023/09/20 01:00 | Leo Vithoontien v Keisuke Saitoh | 6-4,6-3 |
| ITF M25 Sapporo | 2023/09/12 03:45 | Keisuke Saitoh v Tomohiro Masabayashi | 5-7,3-6 |
| ITF M25 Sapporo | 2023/09/06 01:00 | Keisuke Saitoh v Tomohiro Masabayashi | 4-6,6-3,1-6 |
| ITF M25 Hong Kong | 2023/08/31 02:00 | Naoki Nakagawa v Keisuke Saitoh | 6-4,6-7,6-1 |
| ITF M25 Hong Kong | 2023/08/30 02:00 | Keisuke Saitoh v Ji Hoon Son | 6-3,7-6 |
| ITF M15 Caloundra | 2023/08/04 00:55 | Isaac Becroft v Keisuke Saitoh | 6-3,6-4 |
| ITF M15 Caloundra | 2023/08/03 00:50 | Tai Leonard Sach v Keisuke Saitoh | 2-6,1-6 |
| ITF M15 Caloundra | 2023/08/01 04:50 | Keisuke Saitoh v Edward Winter | 7-6,6-2 |