Stadium: Indoor 5 Round: 26 Ground: Hardcourt outdoor
| Challenger Seoul | 2018/05/01 07:05 | Tatsuma Ito v Duckhee Lee | 6-1,6-3 |
| Challenger Kobe | 2017/11/07 04:25 | Duckhee Lee v Tatsuma Ito | 2-6,1-6 |
| Challenger Gimcheon | 2017/05/02 05:55 | Tatsuma Ito v Duckhee Lee | 6-4,3-6,4-6 |
| Challenger Shenzhen | 2017/03/14 06:00 | Duckhee Lee v Tatsuma Ito | 6-1,5-7,6-4 |
| Challenger Kaohsiung | 2015/09/21 07:40 | Tatsuma Ito v Duckhee Lee | 4-6,7-6,6-3 |
| Challenger Yokohama | 2019/02/27 03:00 | Tatsuma Ito v Moez Echargui | 6-0,7-5 |
| Challenger Bangkok | 2019/02/15 04:00 | Soonwoo Kwon v Tatsuma Ito | 3-6,6-4,1-6 |
| Challenger Bangkok | 2019/02/14 03:00 | Alejandro Davidovich Fokina v Tatsuma Ito | 6-1,3-6,4-6 |
| Challenger Bangkok | 2019/02/13 03:00 | David Perez Sanz v Tatsuma Ito | 4-6,2-6 |
| Challenger Launceston | 2019/01/31 01:20 | Jay Clarke v Tatsuma Ito | 6-2,6-7,7-5 |
| Challenger Launceston | 2019/01/29 23:00 | Jacob Grills v Tatsuma Ito | 2-6,4-6 |
| Australian Open | 2019/01/14 03:55 | Tatsuma Ito v Daniel Evans | 5-7,1-6,6-7 |
| Australian Open | 2019/01/11 02:35 | Lorenzo Sonego v Tatsuma Ito | 6-7,6-0,6-7 |
| Challenger Yokohama | 2019/02/27 01:00 | Duckhee Lee v Enzo Couacaud | 6-0,6-2 |
| Challenger Yokohama | 2019/02/26 01:00 | Duckhee Lee v Zihao Xia | 6-0,6-3 |
| Challenger Bangkok 1A | 2019/02/19 07:35 | Alejandro Davidovich Fokina v Duckhee Lee | 6-4,6-2 |
| Challenger Bangkok 1A | 2019/02/18 06:35 | Duckhee Lee v Thanapet Chanta | 6-2,7-6 |
| Challenger Bangkok | 2019/02/12 08:15 | Duckhee Lee v Viktor Troicki | 1-6,2-6 |
| Challenger Bangkok | 2019/02/11 03:00 | Wishaya Trongcharoenchaikul v Duckhee Lee | 3-6,3-6 |
| Challenger Chennai | 2019/02/07 05:00 | Duckhee Lee v Nicola Kuhn | 4-6,4-6 |
| Challenger Chennai | 2019/02/05 05:50 | Duckhee Lee v Sumit Nagal | 6-3,6-4 |