Ground: Clay
| ITF Japan F5 | 2015/06/01 02:30 | Ryotaro Matsumura v Soichiro Moritani | 6-2,6-4 |
| ITF Japan F5 | 2015/05/30 01:00 | Ryotaro Matsumura v Shinta Fujii | 6-3,6-1 |
| ITF Japan F4 | 2015/04/01 01:00 | Ryotaro Matsumura v Shuichi Sekiguchi | 2-6,4-6 |
| ITF Japan F4 | 2015/03/31 03:50 | Masaki Sasai v Ryotaro Matsumura | 2-6,2-6 |
| ITF Japan F4 | 2015/03/30 01:00 | Ryotaro Matsumura v Yutaro Matsuzaki | 6-4,6-3 |
| ITF Japan F3 | 2015/03/21 04:00 | Ko Suzuki v Ryotaro Matsumura | 6-0,6-1 |
| ITF USA F9 Qual | 2015/02/22 16:00 | Wil Spencer v Ryotaro Matsumura | 7-6,5-7,6-2 |
| ITF USA F9 Qual | 2015/02/21 19:00 | Ryotaro Matsumura v Kaptan Kaster | 6-2,6-0 |
| ITF Greece F9 | 2015/04/29 10:05 | David Simunek v Keisuke Watanuki | 6-4,6-2 |
| ITF Greece F5 | 2015/04/23 07:00 | Tom Kocevar-Desman v Keisuke Watanuki | 6-3,6-2 |
| ITF Greece F5 | 2015/04/21 10:40 | Charalampos Kapogiannis v Keisuke Watanuki | 6-3,1-6,5-7 |
| ITF Greece F4 | 2015/04/12 11:00 | Keisuke Watanuki v Stefan Frljanic | 6-4,2-6,5-7 |
| ITF Japan F3 | 2015/03/21 02:30 | Issei Okamura v Keisuke Watanuki | 6-2,6-3 |
| ITF Japan F2 | 2015/03/14 00:30 | Soichiro Moritani v Keisuke Watanuki | 6-4,6-2 |
| ITF Japan F1 | 2015/03/09 00:40 | Jarryd Chaplin v Keisuke Watanuki | 6-4,4-6,7-6 |
| ITF Turkey F34 | 2014/09/28 07:00 | Katsuki Nagao v Keisuke Watanuki | 6-3,5-7,7-6 |