| ITF Japan F7 | 2015/06/18 02:00 | Ryota Tanuma v Katsuki Nagao | 6-3,6-1 |
| ITF Japan F7 | 2015/06/17 01:00 | Shunrou Takeshima v Katsuki Nagao | 6-7,3-6 |
| ITF Japan F6 | 2015/06/10 01:30 | Yosuke Watanuki v Katsuki Nagao | 7-6,6-7,6-4 |
| ITF Japan F5 | 2015/06/02 01:00 | Ben Mclachlan v Katsuki Nagao | 6-1,6-2 |
| ITF Guam F1 | 2015/05/30 02:20 | Takao Suzuki v Katsuki Nagao | 2-6,6-4,6-2 |
| ITF Guam F1 | 2015/05/29 01:40 | Katsuki Nagao v Brendan Moore | 2-6,6-4,6-2 |
| ITF Guam F1 | 2015/05/25 01:00 | Katsuki Nagao v Olly Sadler | 6-4,6-4 |
| ITF Thailand F9 | 2015/04/25 04:00 | Katsuki Nagao v Zach Itzstein | 5-7,3-6 |
| ITF Japan F7 Qual | 2015/06/15 00:30 | Koichi Sano v Masaki Osafune | 6-4,6-2 |
| ITF Japan F7 Qual | 2015/06/14 00:00 | Masaki Osafune v Leo Julien Sebaoun | 7-5,6-2 |
| ITF Japan F3 | 2015/03/22 01:00 | Masaki Osafune v Jeamoon Lee | 4-6,3-6 |
| ITF Japan F7 Qual | 2014/06/16 01:00 | Masaki Osafune v Renta Tokuda | 4-6,3-6 |
| ITF Japan F1 | 2014/03/11 02:55 | Arata Onozawa v Masaki Osafune | 4-6,6-1,6-3 |