Stadium: Center Court Round: 45 Ground: Hardcourt indoor
| ITF Japan F8 | 2018/06/09 01:00 | Seita Watanabe v Tomohiro Masabayashi | 7-6,5-7,4-6 |
| Challenger Kobe Qual | 2017/11/04 07:45 | Seita Watanabe v Xin Gao | 6-4,4-6,0-6 |
| ITF Germany F10 | 2018/07/31 10:00 | Manuel Guinard v Takashi Saito | 7-6,0-6,6-1 |
| Challenger Tampere | 2018/07/21 11:05 | Ivan Gakhov v Takashi Saito | 6-1,6-3 |
| Challenger Scheveningen Qual | 2018/07/14 10:00 | Takashi Saito v Alejandro Davidovich Fokina | 3-6,2-6 |
| ITF Japan F8 | 2018/06/13 02:25 | Takashi Saito v Kousuke Ogura | 6-2,4-6,6-1 |
| ITF Japan F7 | 2018/06/10 01:00 | Takashi Saito v Rio Noguchi | 6-3,6-4 |
| ITF Japan F7 | 2018/06/09 03:20 | Takashi Saito v Gengo Kikuchi | 4-6,7-6,6-3 |
| ITF Japan F7 | 2018/06/08 01:00 | Sora Fukuda v Takashi Saito | 1-6,6-2,4-6 |
| ITF Japan F7 | 2018/06/07 02:00 | Kaito Uesugi v Takashi Saito | 6-0,5-7,5-7 |