Stadium: Center Court Round: 25 Ground: Hardcourt outdoor
| ITF Japan F3 | 2016/03/25 03:00 | Duckhee Lee v Shuichi Sekiguchi | 7-5,6-3 |
| Challenger Gimcheon | 2017/05/04 06:00 | Thomas Fabbiano v Duckhee Lee | 6-3,6-2 |
| Challenger Gimcheon | 2017/05/02 05:55 | Tatsuma Ito v Duckhee Lee | 6-4,3-6,4-6 |
| Challenger Taipei | 2017/04/17 11:20 | Ramkumar Ramanathan v Duckhee Lee | 2-6,6-2,6-4 |
| ATP Marrakech Qual | 2017/04/09 13:40 | Gianluigi Quinzi v Duckhee Lee | 6-2,6-3 |
| ATP Marrakech Qual | 2017/04/08 14:00 | Alexander Zhurbin v Duckhee Lee | 3-6,1-6 |
| Challenger Sophia Antipolis | 2017/04/05 11:40 | Duckhee Lee v Jozef Kovalik | 7-5,4-6,4-6 |
| Challenger Quanzhou | 2017/03/23 07:15 | Matteo Berrettini v Duckhee Lee | 6-4,6-7,6-1 |
| Challenger Quanzhou | 2017/03/23 01:30 | Di Wu v Duckhee Lee | 6-7,7-6,2-6 |
| Challenger Seoul Qual | 2017/05/08 02:00 | Lloyd Glasspool v Shuichi Sekiguchi | 3-6,3-6 |
| Challenger Seoul Qual | 2017/05/07 04:20 | Makoto Ochi v Shuichi Sekiguchi | 1-6,1-6 |
| Challenger Seoul Qual | 2017/05/06 06:05 | Yu-Seob Kim v Shuichi Sekiguchi | 1-6,4-6 |
| Challenger Taipei | 2017/04/18 06:20 | Shuichi Sekiguchi v Franko Skugor | 1-6,4-6 |
| ITF China F5 | 2017/04/15 05:35 | Bradley Mousley v Shuichi Sekiguchi | 7-6,7-6 |
| ITF China F5 | 2017/04/13 05:05 | Tsung-Hua Yang v Shuichi Sekiguchi | 2-6,4-6 |
| ITF China F5 | 2017/04/11 06:50 | Yu Chang v Shuichi Sekiguchi | 1-6,5-7 |
| ITF China F4 | 2017/04/09 02:00 | Zhe Li v Shuichi Sekiguchi | 6-3,6-0 |