Stadium: Court 5 Round: 54 Ground: Clay
| ITF Japan F4 | 2018/03/24 02:00 | Masamichi Imamura v Saito, Takashi | 6-4,6-4 |
| ITF Japan F3 | 2018/03/19 02:15 | Masaya Kobayashi v Saito, Takashi | 6-4,4-6,6-4 |
| ITF Japan F3 | 2018/03/18 01:00 | Moritani, Soichiro v Saito, Takashi | 6-3,3-6,0-6 |
| ITF Japan F3 | 2018/03/17 04:00 | Kurita, Kenta v Saito, Takashi | 7-5,3-6,0-6 |
| ITF Japan F2 | 2018/03/13 04:45 | Saito, Takashi v Naoki Nakagawa | 4-6,6-3,1-6 |
| ITF Japan F1 | 2018/03/10 02:00 | Saito, Takashi v Wishaya Trongcharoenchaikul | 4-6,7-5,4-6 |
| ITF Japan F1 | 2018/03/08 03:10 | Ito, Yuichi v Saito, Takashi | 2-6,4-6 |
| ITF Japan F1 | 2018/03/07 01:00 | Saito, Takashi v Makoto Ochi | 6-3,2-6,6-4 |
| ITF Greece F3 | 2018/03/10 07:30 | Moreno, Federico v Onoda, Ken | 6-3,6-4 |
| ITF Greece F2 | 2018/03/04 08:00 | Duje Ajdukovic v Onoda, Ken | 7-5,7-6 |
| ITF Greece F2 | 2018/03/03 07:30 | Onoda, Ken v Lavdas, Andreas Anastasis | 6-1,6-2 |
| Turkey F8, Singles Qualifying | 2018/02/27 07:30 | Felipe Meligeni Rodrigues Alves v Onoda, Ken | 6-4,6-2 |
| Turkey F8, Singles Qualifying | 2018/02/25 07:30 | Amar, Ran v Onoda, Ken | 3-6,5-7 |
| Turkey F8, Singles Qualifying | 2018/02/24 09:30 | Busch, Ruben v Onoda, Ken | 2-6,2-6 |
| Indonesia F8, Singles | 2017/11/28 03:30 | Onoda, Ken v Yu, Cheng-Yu | 1-6,2-6 |
| Indonesia F8, Singles Qualifying | 2017/11/26 03:30 | Onoda, Ken v Chong, Jun | 6-0,6-2 |