| Australian Open | 01/15 02:00 | 44 | [233] Duckhee Lee v Alessandro Giannessi [145] | 2-6,7-5,7-6 | |
| Australian Open - Wild card | 12/07 04:30 | 28 | [128] Jason Jung v Duckhee Lee [250] | 6-2,6-1 | |
| Australian Open - Wild card | 12/06 02:00 | 27 | [359] Ze Zhang v Duckhee Lee [250] | 5-7,3-6 | |
| Australian Open - Wild card | 12/05 02:00 | 26 | [250] Duckhee Lee v Sho Shimabukuro [445] | 6-2,6-1 | |
| ITF M15 - Nonthaburi | 12/01 02:55 | 29 | [250] Duckhee Lee v Shintaro Imai [307] | 6-1,6-4 | |
| ITF M15 - Nonthaburi | 11/30 05:25 | 28 | Duckhee Lee v Florent Bax | 6-1,6-1 | |
| ITF M15 - Nonthaburi | 11/29 03:00 | 27 | Duckhee Lee v Keisuke Saitoh | 6-2,6-1 | |
| ITF M15 - Nonthaburi | 11/28 04:40 | 26 | [250] Duckhee Lee v Blake Ellis [237] | 6-3,6-1 | |
| ITF M15 - Nonthaburi | 11/27 02:30 | 25 | Duckhee Lee v Naoki Nakagawa | 6-1,6-4 | |
| Challenger Pune | 11/14 08:45 | 26 | [260] Duckhee Lee v Jay Clarke [170] | 1-6,4-6 | |
| Challenger Pune | 11/13 08:05 | 25 | [260] Duckhee Lee v Aziz Dougaz [461] | 6-3,6-4 | |
| Challenger Kobe | 11/05 02:50 | 25 | [255] Duckhee Lee v Shintaro Imai [370] | 4-6,2-6 | |
| Challenger Shenzhen 2 | 10/29 03:10 | 25 | [87] Soonwoo Kwon v Duckhee Lee [257] | 6-2,6-2 | |
| Challenger Shenzhen 2 | 10/28 05:10 | 24 | [283] Kaichi Uchida v Duckhee Lee [257] | 5-7,1-6 | |
| Challenger Liuzhou | 10/22 03:35 | 25 | Duckhee Lee v Jie Cui | 2-6,4-6 | |
| ATP Winston-Salem | 08/20 19:10 | 25 | [212] Duckhee Lee v Hubert Hurkacz [41] | 6-4,0-6,3-6 | |
| ATP Winston-Salem | 08/19 19:00 | 24 | [212] Duckhee Lee v Henri Laaksonen [120] | 7-6,6-1 | |
| Challenger Vancouver | 08/14 17:00 | 25 | [208] Duckhee Lee v Malek Jaziri [99] | 6-2,4-6,1-6 | |
| Challenger Vancouver | 08/13 17:00 | 24 | [208] Duckhee Lee v Maverick Banes [226] | 6-1,6-4 | |
| Challenger Aptos | 08/05 19:55 | 24 | [197] Maxime Janvier v Duckhee Lee [199] | 6-4,4-6,6-4 | |
| Challenger Lexington | 08/02 23:40 | 27 | [194] Jannik Sinner v Duckhee Lee [203] | 4-6,6-3,6-1 | |
| Challenger Lexington | 08/01 14:00 | 26 | [255] Evgeny Karlovskiy v Duckhee Lee [203] | 6-4,2-6,4-6 | |
| Challenger Lexington | 07/30 16:25 | 25 | Nicolas Moreno De Alboran v Duckhee Lee | 2-6,3-6 | |
| Challenger Binghamton | 07/26 15:00 | 27 | [211] Duckhee Lee v Joao Menezes [238] | 5-7,2-6 | |
| Challenger Binghamton | 07/25 17:35 | 26 | [389] Teymuraz Gabashvili v Duckhee Lee [211] | 4-6,3-6 | |
| Challenger Binghamton | 07/24 21:00 | 25 | [262] Aleksandar Vukic v Duckhee Lee [211] | 3-6,3-6 | |
| Challenger Gatineau | 07/19 20:00 | 27 | [213] Duckhee Lee v Jason Kubler [211] | 2-6,3-6 | |
| Challenger Gatineau | 07/18 22:30 | 26 | [433] Alexis Galarneau v Duckhee Lee [213] | 3-6,5-7 | |
| Challenger Gatineau | 07/16 14:00 | 25 | [277] Ernesto Escobedo v Duckhee Lee [213] | 4-6,6-4,6-7 | |
| Challenger Milan | 06/26 09:30 | 25 | [218] Duckhee Lee v Danilo Petrovic [285] | 2-6,2-6 |