Stadium: Court 3 Round: 25 Ground: Hardcourt outdoor
| ITF Japan F3 | 2018/03/18 01:00 | Shinji Hazawa v Kawakami, Rimpei | 6-3,6-3 |
| ITF Japan F3 | 2018/03/17 04:00 | Shinji Hazawa v Maesaki, Naoya | 4-6,6-2,6-1 |
| ITF Japan F1 | 2018/03/08 05:35 | Shinji Hazawa v Moritani, Soichiro | 6-7,2-6 |
| ITF Japan F1 | 2018/03/07 04:45 | Issei Okamura v Shinji Hazawa | 6-3,1-6,3-6 |
| ITF Japan F1 | 2018/03/05 01:00 | Shinji Hazawa v Masamichi Imamura | 4-6,7-5,6-4 |
| Challenger Yokohama | 2018/03/01 02:00 | Yasutaka Uchiyama v Shinji Hazawa | 6-3,7-5 |
| Challenger Yokohama | 2018/02/27 01:00 | Shinji Hazawa v Soonwoo Kwon | 6-3,4-6,7-6 |
| ITF China F1 | 2018/01/13 04:25 | Wang, Huixin v Shinji Hazawa | 3-6,6-0,6-2 |
| ITF Japan F2 | 2018/03/13 02:00 | Kaito Uesugi v Niki, Takuto | 6-0,6-3 |
| ITF Japan F1 | 2018/03/10 02:00 | Nguyen, Daniel v Niki, Takuto | 6-3,6-4 |
| ITF Japan F1 | 2018/03/09 02:00 | Niki, Takuto v Moritani, Soichiro | 6-1,6-4 |
| ITF Japan F1 | 2018/03/08 03:10 | Niki, Takuto v Kibi, Yuya | 6-3,7-5 |
| ITF Japan F1 | 2018/03/07 04:45 | Niki, Takuto v Maesaki, Naoya | 6-2,6-7,6-2 |
| Yokohama, Japan, Qualifying | 2018/02/25 02:35 | Yunseong Chung v Niki, Takuto | 6-7,6-3,6-3 |
| Yokohama, Japan, Qualifying | 2018/02/24 07:05 | Niki, Takuto v Balaji, N. Sriram | 3-6,7-6,7-5 |
| Challenger Kyoto Qual | 2018/02/19 03:45 | Blake Ellis v Niki, Takuto | 6-3,6-4 |