Round: 25 Ground: Clay
| ITF Japan F5 | 2014/06/04 01:00 | Hiromasa Oku v Katsuki Nagao | 7-6,7-6 |
| ITF Japan F4 | 2016/03/30 03:25 | Masato Shiga v Hiromasa Oku | 6-4,6-3 |
| ITF Japan F3 | 2016/03/20 01:00 | Hiromasa Oku v Gengo Kikuchi | 2-6,1-6 |
| ITF Japan F3 | 2016/03/19 03:45 | Hiromasa Oku v Ko Suzuki | 5-7,7-6,7-5 |
| ITF Japan F2 | 2016/03/13 01:00 | Hiromasa Oku v Shintaro Imai | 1-6,0-6 |
| ITF Japan F2 | 2016/03/12 02:00 | Hiromasa Oku v Yutaro Matsuzaki | 6-4,5-7,6-3 |
| ITF Japan F1 | 2016/03/10 01:00 | Hiromasa Oku v Shintaro Imai | 6-3,2-6,1-6 |
| ITF Japan F8 | 2015/06/24 01:10 | Hiromasa Oku v Sho Katayama | 6-7,0-6 |
| ITF Japan F7 | 2015/06/19 03:00 | Hiromasa Oku v Yusuke Watanuki | 2-6,3-6 |
| ITF Japan F4 | 2016/03/28 01:00 | Katsuki Nagao v Sanhui Shin | 1-6,1-6 |
| ITF Japan F4 | 2016/03/27 01:00 | Katsuki Nagao v Masaki Osafune | 6-1,6-2 |
| ITF Japan F3 | 2016/03/20 01:00 | Yuya Ito v Katsuki Nagao | 6-3,6-4 |
| ITF Japan F3 | 2016/03/19 03:45 | Ryota Kishi v Katsuki Nagao | 1-6,5-7 |
| ITF Japan F2 | 2016/03/15 01:00 | Katsuki Nagao v Hiroka Kondo | 6-7,0-6 |
| ITF Japan F2 | 2016/03/13 01:00 | Katsuki Nagao v Ken Onoda | 6-3,5-7,6-4 |
| ITF Japan F1 | 2016/03/10 02:45 | Katsuki Nagao v Yusuke Watanuki | 1-6,6-2,1-6 |
| ITF Japan F1 | 2016/03/07 01:00 | Katsuki Nagao v Soichiro Moritani | 6-4,7-6 |