Round: 26 Ground: Clay
| ITF Vietnam F4 | 2016/09/12 03:00 | Onozawa, Arata v Sano, Koichi | 2-6,7-6,6-0 |
| ITF Japan F8 | 2017/06/14 03:00 | 니클레스, 조한 v Onozawa, Arata | 1-6,0-6 |
| ITF Japan F7 | 2017/06/06 01:00 | Onozawa, Arata v Sasai, Masaki | 6-3,2-6,3-6 |
| ITF Japan F6 | 2017/05/30 03:30 | Sakai, Yuto v Onozawa, Arata | 7-6,7-5 |
| ITF Singapore F1 Qual | 2017/05/21 04:00 | Onozawa, Arata v Look, Michael | 4-6,7-6,4-6 |
| ITF Japan F3 | 2017/03/19 01:00 | Onozawa, Arata v 카와카미, 림페이 | 3-6,6-2,2-6 |
| ITF Japan F3 | 2017/03/18 06:00 | Onozawa, Arata v 푸지이, 소타 | 6-4,6-3 |
| Challenger Kyoto Qual | 2017/02/19 05:25 | Wang, Jimmy v Onozawa, Arata | 6-3,6-4 |
| Challenger Kyoto Qual | 2017/02/18 07:35 | Onozawa, Arata v 타카하시, 유스케 | 6-3,6-7,6-3 |
| ITF Japan F8 | 2017/06/14 03:55 | Sano, Koichi v Higa, Akito | 6-3,6-4 |
| ITF Japan F5 | 2017/04/04 00:30 | Matsuo, Yuki v Sano, Koichi | 7-5,7-6 |
| ITF Japan F5 | 2017/04/02 01:00 | Sano, Koichi v 카와카미, 림페이 | 6-1,6-2 |
| ITF Japan F5 | 2017/04/01 02:00 | Sano, Koichi v Vu, Artem | 6-2,6-4 |
| ITF Japan F4 | 2017/03/25 03:00 | Sano, Koichi v Ono, Yohei | 3-6,1-6 |
| ITF Japan F3 | 2017/03/18 00:30 | Matsuo, Yuki v Sano, Koichi | 6-4,7-6 |
| ITF Japan F2 | 2017/03/14 06:05 | 키쿠치, 겐고 v Sano, Koichi | 6-2,6-4 |
| ITF Japan F2 | 2017/03/13 01:00 | Johns, Collin v Sano, Koichi | 5-7,6-4,4-6 |