Stadium: Court 2 Round: 54 Ground: Synthetic outdoor
| ITF M15 Antalya | 2019/04/01 07:00 | Dan Alexandru Tomescu v Kosuke Okagaki | 6-3,6-4 |
| ITF M15 Antalya | 2019/03/26 07:00 | Kosuke Okagaki v Wilson Leite | 5-7,7-5,2-6 |
| ITF M15 Antalya | 2019/03/11 07:15 | Kosuke Okagaki v Louroi Martinez | 3-6,6-2,5-10 |
| ITF M15 Antalya | 2019/02/25 14:45 | Mircea-Alexandru Jecan v Kosuke Okagaki | 6-4,6-0 |
| ITF M15 Antalya | 2019/02/25 07:00 | Kosuke Okagaki v Moritz Thiem | 3-6,7-6,10-3 |
| ITF Japan F1 | 2018/03/03 01:00 | Kosuke Okagaki v Naoto Kai | 6-4,0-6,2-6 |
| ITF Spain F31 | 2017/09/25 09:00 | Kosuke Okagaki v Alberto C Sanchez | 1-6,2-6 |
| ITF M15 Guam | 2019/06/06 00:00 | Soichiro Moritani v Sam Ryan Ziegann | 6-2,6-2 |
| ITF M15 Guam | 2019/06/04 00:00 | Sam Ryan Ziegann v Marcus Kallioniemi | 6-0,6-0 |
| ITF M15 Karuizawa | 2019/05/28 01:00 | Kento Takeuchi v Sam Ryan Ziegann | 6-3,6-3 |
| ITF M25 Nonthaburi | 2019/05/20 04:40 | Jayden Court v Sam Ryan Ziegann | 6-4,7-5 |
| ITF M15 Mornington | 2019/03/24 23:00 | Kazuma Kawachi v Sam Ryan Ziegann | 6-2,6-1 |
| ITF Thailand F9 | 2018/11/10 05:00 | Vladislav Dubinsky v Sam Ryan Ziegann | 7-6,6-4 |
| ITF Thailand F8 | 2018/11/03 04:30 | Sam Ryan Ziegann v Takuya Kumasaka | 2-6,1-6 |
| ITF Thailand F7 | 2018/10/28 03:00 | Sanhui Shin v Sam Ryan Ziegann | 6-2,6-1 |