Stadium: Court 16 Round: 25 Ground: Clay
| ITF Singapore F1 | 2017/05/25 02:00 | Issei Okamura v Kazuki Nishiwaki | 6-7,1-6 |
| ITF Japan F6 Qual | 2018/04/09 02:50 | Kazuki Nishiwaki v Arata Onozawa | 7-5,6-3 |
| ITF Japan F6 Qual | 2018/04/08 04:00 | Rio Noguchi v Kazuki Nishiwaki | 6-2,6-7,0-6 |
| ITF Japan F6 Qual | 2018/04/07 01:00 | Tamaki Yamao v Kazuki Nishiwaki | 6-4,3-6,3-6 |
| ITF Egypt F10 | 2018/03/21 10:00 | Kazuki Nishiwaki v Benjamin Lock | 6-7,4-6 |
| ITF Egypt F10 | 2018/03/19 08:00 | Michel Vernier v Kazuki Nishiwaki | 3-6,2-6 |
| ITF Egypt F10 | 2018/03/18 12:00 | Bruno Britez v Kazuki Nishiwaki | 6-7,2-6 |
| ITF Egypt F10 | 2018/03/17 14:30 | Kazuki Nishiwaki v Anton Chekhov | 6-2,6-2 |
| ITF Egypt F9 | 2018/03/15 10:30 | Benjamin Lock v Kazuki Nishiwaki | 6-2,6-3 |
| ITF Japan F6 Qual | 2018/04/09 01:00 | Issei Okamura v Yuto Sakai | 6-2,6-3 |
| ITF Japan F6 Qual | 2018/04/08 01:00 | Issei Okamura v Hikaru Shiraishi | 6-4,6-3 |
| 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 |