Round: 25 Ground: Hardcourt outdoor
| ITF USA F6 | 2017/02/03 15:00 | Naoki Nakagawa v Renta Tokuda | 1-6,2-6 |
| Challenger Qujing Qual | 2018/03/18 03:00 | Renta Tokuda v Martins Podzus | 7-6,6-7,3-6 |
| Challenger Shenzhen Qual | 2018/03/12 04:45 | Jason Kubler v Renta Tokuda | 6-1,7-6 |
| Challenger Shenzhen Qual | 2018/03/11 03:10 | Toshihide Matsui v Renta Tokuda | 2-6,3-6 |
| Challenger Zhuhai Qual | 2018/03/05 02:00 | Yusuke Takahashi v Renta Tokuda | 6-4,6-4 |
| Challenger Zhuhai Qual | 2018/03/04 04:35 | Igor Zelenay v Renta Tokuda | 6-7,3-6 |
| Challenger Zhuhai Qual | 2018/03/03 04:50 | Xin Gao v Renta Tokuda | 3-6,1-6 |
| Challenger Yokohama Qual | 2018/02/24 02:35 | Tung-Lin Wu v Renta Tokuda | 6-1,6-4 |
| Challenger Launceston Qual | 2018/02/05 01:05 | Marinko Matosevic v Renta Tokuda | 6-1,4-6,6-4 |
| ITF Japan F3 | 2018/03/20 06:00 | Tatsuma Ito v Naoki Nakagawa | 6-2,6-3 |
| ITF Japan F2 | 2018/03/16 03:10 | Tung-Lin Wu v Naoki Nakagawa | 6-3,4-6,6-2 |
| ITF Japan F2 | 2018/03/14 02:50 | Naoki Nakagawa v Yuta Shimizu | 4-6,6-3,6-2 |
| ITF Japan F2 | 2018/03/13 04:45 | Takashi Saito v Naoki Nakagawa | 4-6,6-3,1-6 |
| ITF Japan F1 | 2018/03/09 02:00 | Naoki Nakagawa v Daniel Nguyen | 6-3,3-6,5-7 |
| ITF Japan F1 | 2018/03/08 01:30 | Naoki Nakagawa v Gengo Kikuchi | 7-5,7-6 |
| ITF Japan F1 | 2018/03/06 02:00 | Naoki Nakagawa v Shin Yoshida | 6-4,6-1 |
| Challenger Kyoto Qual | 2018/02/18 02:45 | Naoki Nakagawa v Ko Suzuki | 6-7,6-7 |