Estádio: Court 7 Round: 25 Ground: Hardcourt outdoor
| Challenger - Yokkaichi | 2019/08/06 01:00 | Courtney John Lock v Kazuki Nishiwaki | 2-6,2-6 |
| ITF - M15 Singapura | 2019/06/15 03:00 | Jonathan Gray v Kazuki Nishiwaki | 6-3,7-5 |
| ITF - M15 Singapura | 2019/06/14 05:30 | Kazuki Nishiwaki v Benard Bruno Nkomba | 6-3,6-0 |
| ITF - M15 Singapura | 2019/06/13 02:00 | Kazuki Nishiwaki v Abhinav Sanjeev Shanmugam | 7-6,6-2 |
| ITF - M15 Singapura | 2019/06/11 07:45 | Kazuki Nishiwaki v Shamirul S Mohd Adam Das | 6-0,6-1 |
| ITF - M15 Singapura | 2019/06/04 02:00 | Cameron Green v Kazuki Nishiwaki | 7-6,6-1 |
| ITF - M15 Singapura | 2019/05/29 03:55 | Maksim Tikhomirov v Kazuki Nishiwaki | 6-3,6-4 |
| ITF - M25 Wuhan | 2019/05/06 02:00 | Kazuki Nishiwaki v Jianhui Li | 5-7,6-2,6-10 |
| Challenger - Chengdu | 2019/07/30 08:05 | Yusuke Takahashi v Yan Bai | 4-6,2-6 |
| Challenger - Chengdu | 2019/07/29 10:45 | Issei Okamura v Yusuke Takahashi | 1-6,2-6 |
| ITF - M25 Taipé | 2019/07/26 02:00 | Yusuke Takahashi v Renta Tokuda | 1-6,5-7 |
| ITF - M25 Taipé | 2019/07/25 04:30 | Yusuke Takahashi v Jumpei Yamasaki | 6-2,6-2 |
| ITF - M25 Taipé | 2019/07/24 02:00 | Yusuke Takahashi v Lucas Renard | 5-7,7-6,6-2 |
| ITF - M25 Taipé | 2019/07/18 10:10 | Cheng-Yu Yu v Yusuke Takahashi | 7-5,6-2 |
| ITF - M25 Taipé | 2019/07/16 06:25 | Chang-Lin Tsai v Yusuke Takahashi | 6-7,1-6 |
| ITF - M25 Yinchuan | 2019/06/25 03:40 | Weiqiang Zheng v Yusuke Takahashi | 6-4,6-2 |