Stadium: Court 3 Round: 26 Ground: Hardcourt outdoor
| ITF M15 Yanagawa | 2023/12/20 02:30 | Seita Watanabe v Hayato Matsuoka | 7-5,6-2 |
| ITF M25 Kalaburagi | 2023/12/01 04:00 | David Pichler v Seita Watanabe | 6-2,6-0 |
| ITF M25 Kalaburagi | 2023/11/30 07:45 | Seita Watanabe v Rishi Reddy | 6-2,6-3 |
| ITF M25 Mumbai | 2023/11/22 03:30 | Seita Watanabe v Louis Wessels | 4-6,5-7 |
| ITF M25 Takasaki | 2023/09/20 01:00 | Naoki Nakagawa v Seita Watanabe | 6-3,6-2 |
| ITF M25 Takasaki | 2023/09/18 03:30 | Mitsuki Wei Kang Leong v Seita Watanabe | 4-6,4-6 |
| ITF M25 Sapporo | 2023/09/15 00:55 | Naoki Nakagawa v Seita Watanabe | 6-3,6-2 |
| ITF M25 Sapporo | 2023/09/13 03:00 | Seita Watanabe v Yuta Kikuchi | 6-1,6-3 |
| ITF M15 Santo Domingo | 2023/11/12 13:00 | Karim Al-Amin v Shu Matsuoka | 7-6,6-2 |
| ITF M25 Santo Domingo | 2023/11/05 13:00 | Matteo Covato v Shu Matsuoka | 7-6,2-6,10-7 |
| UTR Pro Osaka | 2023/07/28 09:15 | Brody Nejedly-Krall v Shu Matsuoka | 1-6,3-6 |
| UTR Pro Osaka | 2023/07/27 06:00 | Hiromasa Koyama v Shu Matsuoka | 1-6,4-6 |
| UTR Pro Osaka | 2023/07/24 05:30 | Shu Matsuoka v Ryoma Matsushita | 3-6,5-7 |
| ITF M15 Monastir | 2023/07/17 07:30 | S Mert Ozdemir v Shu Matsuoka | 1-6,1-6 |
| ITF M15 Monastir | 2023/07/16 15:00 | Shu Matsuoka v Maksim Shin | 3-6,6-1,10-5 |
| ITF M15 Monastir | 2023/07/09 08:30 | Shu Matsuoka v Sanjar Fayziev | 6-3,2-6,5-10 |