Stadium: Sub Court B Round: 26 Ground: Hardcourt outdoor
| ITF M15 Hinode | 2024/03/11 01:00 | Hiromasa Koyama v Hong Kit Wong | 7-6,3-6,4-10 |
| UTR Pro Noda | 2023/08/26 00:00 | Hiromasa Koyama v Paul Howe | 6-7,6-7 |
| UTR Pro Noda | 2023/08/25 00:00 | Hiromasa Koyama v Hiiro Sakamoto | 1-6,1-6 |
| UTR Pro Noda | 2023/08/23 06:30 | Hiromasa Koyama v Yuta Tomida | 1-6,3-6 |
| UTR Pro Osaka | 2023/07/30 04:30 | Koki Ohnuma v Hiromasa Koyama | 6-3,5-2 |
| UTR Pro Osaka | 2023/07/28 06:54 | Hiromasa Koyama v Ryoma Matsushita | 1-6,2-6 |
| UTR Pro Osaka | 2023/07/27 06:00 | Hiromasa Koyama v Shu Matsuoka | 1-6,4-6 |
| UTR Pro Osaka | 2023/07/25 00:30 | Brody Nejedly-Krall v Hiromasa Koyama | 6-2,6-3 |
| ITF M25 Kursumlijska Banja | 2024/06/04 10:50 | Saba Purtseladze v Keisuke Saitoh | 6-3,6-4 |
| ITF M15 Kursumlijska Banja | 2024/05/28 09:30 | Yanaki Milev v Keisuke Saitoh | 6-2,6-4 |
| ITF M15 Kursumlijska Banja | 2024/05/23 11:55 | Hayato Matsuoka v Keisuke Saitoh | 6-4,6-4 |
| ITF M15 Kursumlijska Banja | 2024/05/22 07:00 | Milos Mikovic v Keisuke Saitoh | 1-6,0-6 |
| ITF M15 Kursumlijska Banja | 2024/05/17 07:00 | Keisuke Saitoh v Edas Butvilas | 6-7,6-3,2-6 |
| ITF M15 Kursumlijska Banja | 2024/05/16 07:00 | Keisuke Saitoh v Ignacio Parisca | 7-6,6-1 |
| ITF M15 Kursumlijska Banja | 2024/05/14 09:55 | Daisuke Sumizawa v Keisuke Saitoh | 4-6,7-5,3-6 |
| ITF M25 Kursumlijska Banja | 2024/05/09 07:00 | Keisuke Saitoh v Peter Buldorini | 6-1,1-6,1-6 |