| ITF Japan F6 Qual | 05/29 04:00 | 54 | Keisuke Watanuki v Sho Shimabukuro | 6-1,6-0 | |
| ITF Japan F6 Qual | 05/28 01:00 | 54 | Keisuke Watanuki v Shin Yoshida | 6-1,6-4 | |
| ITF Japan F5 | 04/06 03:40 | 25 | Keisuke Watanuki v Sho Katayama | 2-6,5-7 | |
| ITF Japan F4 | 03/29 05:10 | 25 | Keisuke Watanuki v Shintaro Imai | 3-6,6-3,1-6 | |
| ITF Japan F4 | 03/28 01:00 | 62 | Gengo Kikuchi v Keisuke Watanuki | 2-6,7-5,6-7 | |
| ITF Japan F4 | 03/27 01:00 | 62 | Yusuke Takahashi v Keisuke Watanuki | 4-6,3-6 | |
| ITF Japan F3 | 03/22 03:10 | 25 | Ken Onishi v Keisuke Watanuki | 2-6,6-2,7-5 | |
| ITF Japan F3 | 03/20 02:30 | 44 | Masato Shiga v Keisuke Watanuki | 4-6,6-2,3-6 | |
| ITF Japan F3 | 03/19 03:45 | 44 | Rigele Te v Keisuke Watanuki | 2-6,1-6 | |
| ITF Japan F2 | 03/15 04:30 | 25 | Keisuke Watanuki v Yuya Kibi | 2-6,6-4,1-6 | |
| ITF Japan F2 | 03/13 01:00 | 54 | Aoran Wang v Keisuke Watanuki | 0-6,4-6 | |
| ITF Japan F2 | 03/12 00:30 | 54 | Keisuke Numajiri v Keisuke Watanuki | 6-2,2-6,1-6 | |
| ITF Japan F1 | 03/10 02:35 | 25 | Takuto Niki v Keisuke Watanuki | 7-5,6-2 | |
| ITF Japan F1 | 03/07 01:00 | 62 | Keisuke Watanuki v Kazuma Kawachi | 6-1,6-1 | |
| ITF Japan F1 | 03/06 03:00 | 62 | Keisuke Watanuki v Sora Fukuda | 6-1,3-6,6-3 | |
| ITF Japan F1 | 03/05 03:00 | 62 | Keisuke Watanuki v Yuichiro Inui | 6-2,6-3 | |
| ITF Japan F8 | 06/26 05:05 | - | Katsuki Nagao v Keisuke Watanuki | Retired | |
| ITF Japan F8 | 06/25 01:00 | - | Keisuke Numajiri v Keisuke Watanuki | 3-6,3-6 | |
| ITF Japan F8 | 06/24 02:45 | - | Keisuke Watanuki v Yuichi Ito | 6-1,7-5 | |
| ITF Japan F7 | 06/16 02:15 | - | Arata Onozawa v Keisuke Watanuki | 7-6,0-6,6-3 | |
| ITF Japan F6 | 06/11 02:55 | - | Takuto Niki v Keisuke Watanuki | 6-7,7-6,6-4 | |
| ITF Japan F6 | 06/10 01:30 | - | Keisuke Watanuki v Hiromasa Oku | 6-2,6-3 | |
| ITF Japan F5 | 06/04 02:00 | - | Thomas Fancutt v Keisuke Watanuki | 7-5,7-6 | |
| ITF Japan F5 | 06/03 06:30 | - | Ryotaro Matsumura v Keisuke Watanuki | 6-2,4-6,0-6 | |
| ITF Greece F9 | 04/29 10:05 | - | David Simunek v Keisuke Watanuki | 6-4,6-2 | |
| ITF Greece F5 | 04/23 07:00 | - | Tom Kocevar-Desman v Keisuke Watanuki | 6-3,6-2 | |
| ITF Greece F5 | 04/21 10:40 | - | Charalampos Kapogiannis v Keisuke Watanuki | 6-3,1-6,5-7 | |
| ITF Greece F4 | 04/12 11:00 | - | Keisuke Watanuki v Stefan Frljanic | 6-4,2-6,5-7 | |
| ITF Japan F3 | 03/21 02:30 | - | Issei Okamura v Keisuke Watanuki | 6-2,6-3 | |
| ITF Japan F2 | 03/14 00:30 | - | Soichiro Moritani v Keisuke Watanuki | 6-4,6-2 |