Stadium: Court 3 Round: 45
| ITF Hong Kong F3 | 2017/07/05 06:25 | Jacob Grills v Jumpei Yamasaki | 6-2,4-6,6-0 |
| Challenger Gimcheon Qual | 2018/05/06 07:10 | Yoshihito Nishioka v Jacob Grills | 6-2,0-6,7-6 |
| Challenger Gimcheon Qual | 2018/05/05 05:20 | Jacob Grills v Jung-Woong Na | 5-7,6-4,6-3 |
| Challenger Seoul Qual | 2018/04/30 05:00 | Renta Tokuda v Jacob Grills | 6-3,6-2 |
| Challenger Seoul Qual | 2018/04/29 04:15 | Jae Hwan Kim v Jacob Grills | 6-4,2-6,4-6 |
| Challenger Taipei | 2018/04/10 11:50 | Jason Jung v Jacob Grills | 6-0,6-3 |
| Challenger Taipei Qual | 2018/04/09 03:00 | Ruan Roelofse v Jacob Grills | 6-4,2-6,7-6 |
| Challenger Taipei Qual | 2018/04/08 03:00 | Cheng-Yu Yu v Jacob Grills | 6-4,5-7,3-6 |
| Challenger Taipei Qual | 2018/04/07 02:00 | Jacob Grills v Yunseong Chung | 6-3,2-6,6-2 |
| ITF China F5 | 2018/05/10 03:00 | Cheong-Eui Kim v Jumpei Yamasaki | 2-6,5-7 |
| ITF China F5 | 2018/05/09 02:00 | Weibowen Zou v Jumpei Yamasaki | 0-6,0-6 |
| ITF Vietnam F1 | 2018/05/03 03:00 | Chun Hsin Tseng v Jumpei Yamasaki | 6-2,6-3 |
| ITF Vietnam F1 | 2018/05/02 03:00 | Niki Kaliyanda Poonacha v Jumpei Yamasaki | 4-6,6-3,1-6 |
| ITF Vietnam F1 | 2018/04/30 06:15 | Justin Barki v Jumpei Yamasaki | 4-6,4-6 |
| ITF Japan F6 | 2018/04/13 03:15 | Renta Tokuda v Jumpei Yamasaki | 4-6,6-2,6-4 |
| ITF Japan F6 | 2018/04/12 01:00 | Jumpei Yamasaki v Xin Gao | 3-6,7-6,6-4 |
| ITF Japan F6 | 2018/04/10 01:00 | Jumpei Yamasaki v Yuya Kibi | 7-6,6-1 |