Round: 26 Ground: Clay
| ITF - Vietnam F4 | 2016/09/12 03:00 | Arata Onozawa v Koichi Sano | 2-6,7-6,6-0 |
| ITF - Japan F8 | 2017/06/14 03:00 | Johan Nikles v Arata Onozawa | 1-6,0-6 |
| ITF - Japan F7 | 2017/06/06 01:00 | Arata Onozawa v Masaki Sasai | 6-3,2-6,3-6 |
| ITF - Japan F6 | 2017/05/30 03:30 | Yuto Sakai v Arata Onozawa | 7-6,7-5 |
| ITF - Singapur F1 - Qualifikation | 2017/05/21 04:00 | Arata Onozawa v Michael Look | 4-6,7-6,4-6 |
| ITF - Japan F3 | 2017/03/19 01:00 | Arata Onozawa v Rimpei Kawakami | 3-6,6-2,2-6 |
| ITF - Japan F3 | 2017/03/18 06:00 | Arata Onozawa v Sota Fujii | 6-4,6-3 |
| Challenger - Kyoto - Qualifikation | 2017/02/19 05:25 | Jimmy Wang v Arata Onozawa | 6-3,6-4 |
| Challenger - Kyoto - Qualifikation | 2017/02/18 07:35 | Arata Onozawa v Yusuke Takahashi | 6-3,6-7,6-3 |
| ITF - Japan F8 | 2017/06/14 03:55 | Koichi Sano v Akito Higa | 6-3,6-4 |
| ITF - Japan F5 | 2017/04/04 00:30 | Yuki Matsuo v Koichi Sano | 7-5,7-6 |
| ITF - Japan F5 | 2017/04/02 01:00 | Koichi Sano v Rimpei Kawakami | 6-1,6-2 |
| ITF - Japan F5 | 2017/04/01 02:00 | Koichi Sano v Artem Vu | 6-2,6-4 |
| ITF - Japan F4 | 2017/03/25 03:00 | Koichi Sano v Yohei Ono | 3-6,1-6 |
| ITF - Japan F3 | 2017/03/18 00:30 | Yuki Matsuo v Koichi Sano | 6-4,7-6 |
| ITF - Japan F2 | 2017/03/14 06:05 | Gengo Kikuchi v Koichi Sano | 6-2,6-4 |
| ITF - Japan F2 | 2017/03/13 01:00 | Collin Johns v Koichi Sano | 5-7,6-4,4-6 |