Stadium: Court 8 Round: 62 Ground: Clay
| ITF China F2 | 2018/01/16 03:40 | Hu Liu v Issei Okamura | 7-5,4-6,2-6 |
| ITF China F1 | 2018/01/11 02:30 | Ryota Tanuma v Issei Okamura | 6-1,6-2 |
| ITF China F1 | 2018/01/09 04:50 | Issei Okamura v Lingxi Zhao | 3-6,6-3,6-4 |
| ITF Vietnam F3 | 2017/11/25 03:00 | Issei Okamura v Arjun Kadhe | 1-6,1-6 |
| ITF Vietnam F3 | 2017/11/24 03:00 | Rio Noguchi v Issei Okamura | 2-6,2-6 |
| ITF Vietnam F3 | 2017/11/22 03:00 | Michael Look v Issei Okamura | 6-7,2-6 |
| ITF Vietnam F3 | 2017/11/21 04:30 | Issei Okamura v Yan Sabanin | 6-4,6-1 |
| Challenger Toyota Qual | 2017/11/11 03:40 | Issei Okamura v Makoto Ochi | 6-7,6-7 |
| ITF Hong Kong F6 | 2017/12/31 03:00 | Yuto Sakai v Alberto Lim | 6-7,4-6 |
| ITF Hong Kong F5 | 2017/12/24 02:00 | Chan-Yeong Oh v Yuto Sakai | 6-3,6-3 |
| ITF Hong Kong F5 | 2017/12/23 02:00 | Yuto Sakai v Congsup Congcar | 6-4,6-4 |
| Challenger Toyota Qual | 2017/11/11 07:35 | Hiroyasu Ehara v Yuto Sakai | 6-7,6-2,6-3 |
| Challenger Toyota Qual | 2017/11/11 02:15 | Yuto Sakai v Masaki Osafune | 7-6,1-6,6-1 |
| Challenger Kobe Qual | 2017/11/04 05:20 | Yuto Sakai v Sora Fukuda | 1-6,3-6 |
| ITF Japan F8 | 2017/06/15 01:00 | Yuto Sakai v Yusuke Watanuki | 4-6,6-3,3-6 |
| ITF Japan F8 | 2017/06/14 01:00 | Yuto Sakai v Yohei Ono | 7-5,6-0 |