Stadium: Court 7 Round: 25 Ground: Synthetic outdoor
| Akishima, Singles M-ITF-JPN-08A | 2019/06/11 05:00 | Takeshima, Shunrou v Okagaki, Kosuke | 2-6,2-6 |
| Akishima, Singles M-ITF-JPN-08A | 2019/06/11 00:00 | Okagaki, Kosuke v Sam Ryan Ziegann | 6-1,6-0 |
| ITF - M15 Antalya | 2019/04/01 07:00 | Dan Alexandru Tomescu v Okagaki, Kosuke | 6-3,6-4 |
| ITF - M15 Antalya | 2019/03/26 07:00 | Okagaki, Kosuke v Wilson Leite | 5-7,7-5,2-6 |
| ITF - M15 Antalya | 2019/03/11 07:15 | Okagaki, Kosuke v Louroi Martinez | 3-6,6-2,5-10 |
| ITF - M15 Antalya | 2019/02/25 14:45 | Mircea-Alexandru Jecan v Okagaki, Kosuke | 6-4,6-0 |
| ITF - M15 Antalya | 2019/02/25 07:00 | Okagaki, Kosuke v Thiem, Moritz | 3-6,7-6,10-3 |
| ITF Japan F1 | 2018/03/03 01:00 | Okagaki, Kosuke v Kai, Naoto | 6-4,0-6,2-6 |
| Akishima, Singles M-ITF-JPN-08A | 2019/06/11 04:45 | Tamaki Yamao v Schouten, Ien | 6-3,7-6 |
| Akishima, Singles M-ITF-JPN-08A | 2019/06/11 00:00 | Tamaki Yamao v Taisei Miyamoto | 6-4,2-6,10-4 |
| ITF - M15 Kashiwa | 2019/04/04 05:30 | Sho Shimabukuro v Tamaki Yamao | 6-2,2-6,6-2 |
| ITF - M15 Kashiwa | 2019/04/03 03:05 | Tamaki Yamao v Naoki Tajima | 6-1,3-6,6-2 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Tanuma, Ryota v Tamaki Yamao | 6-7,4-6 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Tamaki Yamao v Veldheer, Mick | 6-1,6-4 |
| ITF - M15 Tsukuba | 2019/03/25 04:30 | Veldheer, Mick v Tamaki Yamao | 6-1,6-3 |
| ITF - M15 Tsukuba | 2019/03/25 01:00 | Tamaki Yamao v Ng, Hao Yuan | 6-3,6-2 |