Round: 62 Ground: Hardcourt outdoor
| ITF Japan F3 | 2018/03/22 06:55 | Tatsuma Ito v Tanuma, Ryota | 6-7,6-2,6-1 |
| ITF Japan F3 | 2018/03/22 03:00 | Tanuma, Ryota v Sora Fukuda | 6-3,6-2 |
| ITF Japan F3 | 2018/03/19 04:05 | Fujii, Shinta v Tanuma, Ryota | 2-6,2-6 |
| ITF Japan F2 | 2018/03/12 02:30 | Kibi, Yuya v Tanuma, Ryota | 6-2,2-6,7-5 |
| Yokohama, Japan, Qualifying | 2018/02/24 02:45 | Zhe Li v Tanuma, Ryota | 5-7,6-1,6-2 |
| Challenger Kyoto Qual | 2018/02/18 01:00 | Tanuma, Ryota v Fujii, Shinta | 3-6,5-7 |
| Challenger Kyoto Qual | 2018/02/17 01:00 | Tanuma, Ryota v Kazuma Kawachi | 6-3,6-0 |
| ITF China F3 | 2018/01/24 03:00 | Tanuma, Ryota v Nedelko, Ivan | 3-6,5-7 |
| ITF Japan F3 | 2018/03/17 04:00 | Moritani, Soichiro v Shimizu, Kazuki | 6-2,6-3 |
| ITF Japan F1 | 2018/03/03 05:30 | Shimizu, Kazuki v Sasai, Masaki | 3-6,2-6 |
| ITF Turkey F7 | 2018/02/19 08:00 | Sakai, Yuto v Shimizu, Kazuki | 6-2,6-3 |
| ITF Turkey F7 | 2018/02/18 11:30 | Samuelsson, Christian v Shimizu, Kazuki | 6-3,3-6,4-6 |
| ITF Turkey F7 | 2018/02/18 06:30 | Shimizu, Kazuki v Ryan Nijboer | 6-4,3-6,6-4 |
| Turkey F6, Singles Qualifying | 2018/02/13 07:00 | Shimizu, Kazuki v Juan Pablo Varillas | 6-7,4-6 |
| Turkey F6, Singles Qualifying | 2018/02/12 09:00 | Shimizu, Kazuki v Palazov, Zlatan | 6-0,6-4 |
| Turkey F6, Singles Qualifying | 2018/02/11 07:00 | Kim, Cheong Hwi v Shimizu, Kazuki | 5-7,0-6 |