Round: 25 Ground: Hardcourt outdoor
| Challenger Qujing Qual | 2018/03/17 02:00 | Rui-Xuan Wang v Jacob Grills | 3-6,7-6,6-2 |
| Challenger Shenzhen Qual | 2018/03/11 02:45 | Jacob Grills v Yusuke Takahashi | 4-6,6-4,2-6 |
| Challenger Zhuhai Qual | 2018/03/04 03:45 | Jacob Grills v Gerard Granollers-Pujol | 2-6,6-4,2-6 |
| Challenger Zhuhai Qual | 2018/03/03 05:20 | Jacob Grills v Jie Cui | 6-4,7-6 |
| Challenger Launceston Qual | 2018/02/04 02:00 | Benjamin Mitchell v Jacob Grills | 7-5,6-3 |
| Challenger Launceston Qual | 2018/02/03 02:20 | Benjamin Cawston v Jacob Grills | 0-6,1-6 |
| Challenger Burnie Qual | 2018/01/27 06:30 | Gerard Granollers-Pujol v Jacob Grills | 7-5,6-7,6-1 |
| Challenger Burnie Qual | 2018/01/27 02:10 | Jacob Grills v Peter Kobelt | 6-3,6-3 |
| ITF Japan F3 | 2018/03/22 04:05 | Shuichi Sekiguchi v Sho Katayama | 5-7,6-4,2-6 |
| ITF Japan F3 | 2018/03/19 01:00 | Shuichi Sekiguchi v Jumpei Yamasaki | 6-7,7-6,6-2 |
| ITF Japan F2 | 2018/03/12 02:30 | Seong Chan Hong v Shuichi Sekiguchi | 6-4,1-6,7-6 |
| Challenger Yokohama Qual | 2018/02/24 05:10 | Hiroki Moriya v Shuichi Sekiguchi | 6-2,6-4 |
| Challenger Kyoto Qual | 2018/02/17 06:10 | Yuya Kibi v Shuichi Sekiguchi | 6-3,6-2 |
| Challenger Ningbo Qual | 2017/10/15 07:50 | Shuichi Sekiguchi v Yunseong Chung | 4-6,3-6 |
| Challenger Kaohsiung | 2017/10/03 05:40 | Shuichi Sekiguchi v Akira Santillan | 3-6,4-6 |
| Challenger Gwangju | 2017/09/19 01:30 | Shuichi Sekiguchi v Tsung-Hua Yang | 5-7,6-7 |