Ground: Hardcourt outdoor
| ITF Japan F3 | 2014/03/24 01:00 | Yohei Ono v Yuki Nakamura | 6-2,6-1 |
| ITF Japan F2 | 2015/03/18 02:55 | Duckhee Lee v Katsuki Nagao | 6-3,7-5 |
| ITF Japan F2 | 2015/03/16 01:00 | Chih-Jen Ho v Katsuki Nagao | 4-6,4-6 |
| ITF Japan F1 | 2015/03/10 03:50 | Katsuki Nagao v Duckhee Lee | 2-6,3-6 |
| ITF Turkey F34 | 2014/10/01 08:35 | Marshall Tutu v Katsuki Nagao | 6-3,6-1 |
| ITF Turkey F34 | 2014/09/29 07:00 | Katsuki Nagao v Yvo Panak | 6-3,6-0 |
| ITF Turkey F34 | 2014/09/28 07:00 | Katsuki Nagao v Keisuke Watanuki | 6-3,5-7,7-6 |
| ITF Turkey F33 | 2014/09/25 09:40 | Ramkumar Ramanathan v Katsuki Nagao | 6-2,7-5 |
| ITF Turkey F33 | 2014/09/24 07:00 | Issam Haitham Taweel v Katsuki Nagao | 3-6,3-6 |