| ITF Japan F3 | 2014/03/26 02:50 | Takuto Niki v Keisuke Watanuki | 6-3,6-1 |
| ITF China F6 | 2015/05/28 02:00 | Xin Gao v Takuto Niki | 6-2,7-6 |
| ITF China F6 | 2015/05/26 07:25 | Xiao Gong v Takuto Niki | 2-6,2-6 |
| ITF Japan F4 | 2015/04/04 01:30 | Yasutaka Uchiyama v Takuto Niki | 6-1,6-2 |
| ITF Japan F4 | 2015/04/03 01:30 | Zhe Li v Takuto Niki | 2-6,2-6 |
| ITF Japan F4 | 2015/04/02 03:15 | Yong-Kyu Lim v Takuto Niki | 2-6,2-6 |
| ITF Japan F4 | 2015/04/01 03:20 | Yuichi Ito v Takuto Niki | 1-6,4-6 |
| ITF Japan F4 | 2015/03/31 01:00 | Takashi Saito v Takuto Niki | 5-7,7-5,3-6 |
| ITF Japan F3 | 2015/03/27 02:25 | Yong-Kyu Lim v Takuto Niki | 7-6,7-5 |
| ITF Japan F6 | 2015/06/10 01:30 | Keisuke Watanuki v Hiromasa Oku | 6-2,6-3 |
| ITF Japan F5 | 2015/06/04 02:00 | Thomas Fancutt v Keisuke Watanuki | 7-5,7-6 |
| ITF Japan F5 | 2015/06/03 06:30 | Ryotaro Matsumura v Keisuke Watanuki | 6-2,4-6,0-6 |
| 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 |