Round: 62 Ground: Hardcourt outdoor
| ITF Japan F8 | 2015/06/27 01:00 | Yasutaka Uchiyama v Nagao, Katsuki | 7-6,6-3 |
| ITF Japan F8 | 2015/06/25 04:25 | Ehara, Hiroyasu v Nagao, Katsuki | 4-6,3-6 |
| ITF Japan F8 | 2015/06/24 01:10 | Nagao, Katsuki v Osafune, Masaki | 6-3,6-0 |
| ITF Japan F7 | 2015/06/18 02:00 | Tanuma, Ryota v Nagao, Katsuki | 6-3,6-1 |
| ITF Japan F7 | 2015/06/17 01:00 | Takeshima, Shunrou v Nagao, Katsuki | 6-7,3-6 |
| ITF Japan F6 | 2015/06/10 01:30 | Yosuke Watanuki v Nagao, Katsuki | 7-6,6-7,6-4 |
| ITF Japan F5 | 2015/06/02 01:00 | Mclachlan, Ben v Nagao, Katsuki | 6-1,6-2 |
| ITF Guam F1 | 2015/05/30 02:20 | Suzuki, Takao v Nagao, Katsuki | 2-6,6-4,6-2 |