Round: 54 Ground: Clay
| ITF Japan F6 Qual | 2017/05/28 07:00 | Keisuke Watanuki v Yuto Sakai | 6-7,6-7 |
| ITF Japan F6 Qual | 2017/05/28 07:00 | Keisuke Watanuki v Yuto Sakai | 6-7,6-7 |
| ITF Japan F6 Qual | 2017/05/27 01:00 | Keisuke Watanuki v Sung Min Han | 6-4,6-0 |
| ITF Japan F5 | 2017/04/02 01:00 | Masaki Sasai v Keisuke Watanuki | 6-2,6-4 |
| ITF Japan F5 | 2017/04/01 02:00 | Takashi Yasugami v Keisuke Watanuki | 4-6,6-2,5-7 |
| ITF Japan F4 | 2017/03/28 01:00 | Masaya Kobayashi v Keisuke Watanuki | 6-3,6-2 |
| ITF Japan F4 | 2017/03/27 01:00 | Yuga Tashiro v Keisuke Watanuki | 2-6,6-7 |
| ITF Japan F4 | 2017/03/25 03:00 | Yu Chang v Keisuke Watanuki | 7-6,3-6,4-6 |
| ITF Japan F2 | 2017/03/14 04:20 | Yusuke Takahashi v Keisuke Watanuki | 6-2,6-2 |
| ITF Japan F6 Qual | 2017/05/28 07:00 | Keisuke Watanuki v Yuto Sakai | 6-7,6-7 |
| ITF Japan F5 | 2017/04/01 01:00 | Yuto Sakai v Kazuki Nishiwaki | 2-6,6-7 |
| ITF Japan F3 | 2017/03/18 06:00 | Shane Vinsant v Yuto Sakai | 6-3,6-2 |
| ITF Japan F3 | 2017/03/18 00:30 | Naru Shirafuji v Yuto Sakai | 3-6,4-6 |
| ITF Japan F1 | 2017/03/05 01:00 | Masaya Kobayashi v Yuto Sakai | 7-6,7-5 |
| ITF Japan F1 | 2017/03/04 03:30 | Yuto Sakai v Yuki Nakamura | 7-6,7-5 |
| ITF Indonesia F3 | 2017/02/22 06:50 | Yutaro Matsuzaki v Yuto Sakai | 6-4,6-4 |
| ITF Indonesia F3 Qual | 2017/02/20 02:30 | Chien Hsun Lo v Yuto Sakai | 1-6,6-1,6-7 |