Stadium: Court 2 Round: 26 Ground: Hardcourt outdoor
| ITF Thailand F12 Qual | 2017/12/10 03:00 | Ryota Tanuma v Nam, Ji Sung | 4-6,2-6 |
| Challenger - Gwangju | 2019/05/14 06:00 | Nam, Ji Sung v Sugita, Yuichi | 2-6,2-6 |
| Challenger - Gwangju | 2019/05/13 02:00 | Nam, Ji Sung v Rio Noguchi | 6-2,6-1 |
| Challenger - Busan | 2019/05/06 07:40 | Cem Ilkel v Nam, Ji Sung | 6-4,7-6 |
| Challenger Seoul | 2019/05/01 02:00 | Nam, Ji Sung v Ramkumar Ramanathan | 3-6,6-7 |
| Challenger Seoul | 2019/04/30 03:35 | Nam, Ji Sung v Duckhee Lee | 7-5,6-1 |
| Challenger Seoul | 2019/04/29 02:00 | Nam, Ji Sung v Ji Hoon Son | 6-3,6-2 |
| Matsuyama, Singles M-ITF-JPN-06A | 2019/04/12 01:00 | Nam, Ji Sung v Brymer, Gage | 3-6,3-6 |
| Matsuyama, Singles M-ITF-JPN-06A | 2019/04/09 04:55 | Nam, Ji Sung v Mark Whitehouse | 7-6,6-2 |
| Nonthaburi, Singles M-ITF-THA-01A | 2019/05/22 03:00 | Ryota Tanuma v Anton Chekhov | 3-6,7-6,6-3 |
| ITF - M25 Luan | 2019/05/16 03:30 | Ryota Tanuma v Fajing Sun | 5-7,3-6 |
| ITF - M25 Luan | 2019/05/15 04:50 | Linang Xiao v Ryota Tanuma | 4-6,4-6 |
| Wuhan, Qualifications Simples M-ITF-CHN-05A | 2019/05/08 03:15 | Ryota Tanuma v He, Yecong | 4-6,6-3,3-6 |
| Matsuyama, Singles M-ITF-JPN-06A | 2019/04/09 04:10 | Ryota Tanuma v Sekiguchi, Shuichi | 4-6,4-6 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Ryota Tanuma v Seita Watanabe | 3-6,6-1,12-10 |
| ITF - M15 Kashiwa | 2019/04/01 00:00 | Ryota Tanuma v Tamaki Yamao | 6-7,4-6 |
| ITF - M15 Tsukuba | 2019/03/28 01:00 | Ryota Tanuma v Shintaro Imai | 5-7,3-6 |