Round: 62 Ground: Clay
| ITF Japan F5 | 2018/03/31 03:30 | Issei Okamura v Yuta Kawahashi | 3-6,1-6 |
| ITF Japan F4 | 2018/03/26 01:00 | Issei Okamura v Shao-Fan Liu | 3-6,5-7 |
| ITF Japan F4 | 2018/03/24 04:00 | Issei Okamura v Kousuke Ogura | 6-3,7-5 |
| ITF Japan F3 | 2018/03/19 06:40 | Issei Okamura v Makoto Ochi | 6-7,3-6 |
| ITF Japan F3 | 2018/03/18 01:30 | Issei Okamura v Masaki Sasai | 6-3,6-1 |
| ITF Japan F3 | 2018/03/17 04:00 | Issei Okamura v Arata Onozawa | 7-6,6-0 |
| ITF Japan F2 | 2018/03/15 02:35 | Issei Okamura v Kaito Uesugi | 4-6,5-7 |
| ITF Japan F2 | 2018/03/13 00:30 | Issei Okamura v Rimpei Kawakami | 6-2,6-4 |
| ITF Japan F7 | 2016/06/07 05:10 | Yuichi Ito v Hikaru Shiraishi | 6-1,6-0 |