Stadium: Centre Round: 28 Ground: Grass
| Challenger Yokohama Qual | 2017/02/27 01:00 | Brydan Klein v Shuichi Sekiguchi | 7-5,6-2 |
| ITF Slovakia F3 | 2018/08/07 11:25 | Samm Butler v Shuichi Sekiguchi | 6-1,7-6 |
| ITF Austria F3 | 2018/07/16 08:00 | Jorge Panta v Shuichi Sekiguchi | 1-6,7-6,7-5 |
| ITF Czech Republic F6 | 2018/07/10 08:00 | Martin Bugaj v Shuichi Sekiguchi | 6-1,6-2 |
| ITF China F9 | 2018/07/06 03:00 | Min-Kyu Song v Shuichi Sekiguchi | 6-2,6-1 |
| ITF China F9 | 2018/07/05 04:35 | Chenhe Li v Shuichi Sekiguchi | 2-6,5-7 |
| ITF China F9 | 2018/07/03 07:00 | Lingxi Zhao v Shuichi Sekiguchi | 2-6,0-6 |
| Challenger Fergana | 2018/06/19 07:55 | Rubin Statham v Shuichi Sekiguchi | 6-1,6-7,2-6 |
| Challenger Fergana Qual | 2018/06/18 05:00 | Roman Safiullin v Shuichi Sekiguchi | 4-6,6-2,4-6 |
| ITF Australia F8 | 2018/10/09 01:00 | Brydan Klein v Dusty H. Boyer | 5-7,6-3,3-6 |
| ITF Australia F7 | 2018/10/04 02:55 | Dusty H. Boyer v Brydan Klein | 6-4,7-6 |
| ITF Australia F7 | 2018/10/03 00:00 | Scott Puodziunas v Brydan Klein | 2-6,2-6 |
| ITF Australia F6 | 2018/09/28 02:35 | Brydan Klein v Jacob Grills | 6-7,5-7 |
| ITF Australia F6 | 2018/09/27 01:00 | Brydan Klein v Christian Langmo | 6-3,6-3 |
| ITF Australia F6 | 2018/09/26 02:40 | Brydan Klein v Jayden Court | 6-3,6-3 |
| ITF Australia F5 | 2018/09/23 01:00 | Brydan Klein v Jacob Grills | 1-6,7-6,5-7 |
| ITF Australia F5 | 2018/09/22 02:00 | Jeremy Beale v Brydan Klein | 6-3,6-7,4-6 |