Round: 25 Ground: Synthetic outdoor
| ITF Japan F2 | 2015/03/17 04:10 | Masaki Sasai v Arata Onozawa | 6-4,6-4 |
| ITF Japan F6 | 2017/05/30 03:30 | Yuto Sakai v Arata Onozawa | 7-6,7-5 |
| ITF Singapore F1 Qual | 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 Qual | 2017/02/19 05:25 | Jimmy Wang v Arata Onozawa | 6-3,6-4 |
| Challenger Kyoto Qual | 2017/02/18 07:35 | Arata Onozawa v Yusuke Takahashi | 6-3,6-7,6-3 |
| ITF - M15 Monastir | 2016/11/12 07:35 | Kento Takeuchi v Arata Onozawa | 7-6,6-2 |
| ITF - M15 Monastir | 2016/11/12 02:10 | Ken Onishi v Arata Onozawa | 3-6,4-6 |
| ITF Japan F6 | 2017/05/31 01:00 | Renta Tokuda v Masaki Sasai | 6-4,6-3 |
| ITF Japan F6 | 2017/05/30 06:00 | Yuga Tashiro v Masaki Sasai | 1-6,4-6 |
| ITF Japan F5 | 2017/04/04 04:30 | Yusuke Watanuki v Masaki Sasai | 6-2,6-2 |
| ITF Japan F5 | 2017/04/02 01:00 | Masaki Sasai v Keisuke Watanuki | 6-2,6-4 |
| ITF Japan F4 | 2017/03/29 01:00 | Masaki Sasai v Yosuke Watanuki | 7-5,3-6,1-6 |
| ITF Japan F4 | 2017/03/28 01:00 | Masaki Sasai v Teppei Uesugi | 6-3,6-2 |
| ITF Japan F3 | 2017/03/18 06:00 | Hiroyasu Ehara v Masaki Sasai | 6-3,6-4 |
| ITF Japan F2 | 2017/03/17 04:00 | Masaki Sasai v Max Purcell | 3-6,2-6 |