Round: 25 Ground: Clay
| ITF Japan F4 | 2015/03/28 00:30 | Yutaro Matsuzaki v Καζούκι Νισιβάκι | 6-7,6-4,6-4 |
| ITF Japan F2 | 2015/03/14 00:30 | Ριότα Τανούμα v Καζούκι Νισιβάκι | 6-4,6-4 |
| ITF Japan F6 Qual | 2014/06/09 03:00 | Σοχέι Τσικάμι v Καζούκι Νισιβάκι | 6-0,6-3 |
| ITF Japan F5 | 2014/06/04 03:35 | Καζούκι Νισιβάκι v Jui-Chen Hung | 4-6,6-7 |
| ITF Japan F5 | 2014/06/03 01:00 | Shunrou Takeshima v Καζούκι Νισιβάκι | 6-3,5-7,3-6 |
| ITF Japan F7 | 2016/06/07 03:40 | Hiromasa Oku v Σο Καταγιάμα | 1-6,2-6 |
| ITF Japan F6 | 2016/06/02 01:00 | Hiromasa Oku v Yuya Kibi | 3-6,2-6 |
| ITF Japan F6 | 2016/05/31 01:00 | Τακούτο Νίκι v Hiromasa Oku | 2-6,3-6 |
| ITF Guam F1 | 2016/05/24 02:00 | Hiromasa Oku v Shunrou Takeshima | 3-6,2-6 |
| ITF Turkey F19 | 2016/05/13 09:20 | Marc Sieber v Hiromasa Oku | 6-0,6-3 |
| ITF Turkey F19 | 2016/05/11 13:00 | Hiromasa Oku v Thomas Statzberger | 6-3,6-4 |
| ITF Turkey F18 | 2016/05/04 08:00 | Hiromasa Oku v Anil Yuksel | 3-6,2-6 |
| ITF Turkey F17 | 2016/04/26 11:20 | Άλτουγκ Τσελικμπίλεκ v Hiromasa Oku | 6-4,2-6,7-6 |