| UTR Pro Tennis Series Mulheim | 2021/10/13 10:00 | Weng, Jing Long v Sandkaulen, Tim | 3-6,2-5 |
| UTR Pro Tennis Series Mulheim | 2021/10/12 08:30 | Weng, Jing Long v Dzhavakian, Yurii | 5-7,6-1,6-3 |
| UTR Pro Tennis Series Mulheim | 2021/10/11 07:00 | Edison Ambarzumjan v Weng, Jing Long | 1-6,1-6 |
| UTR Pro Tennis Series Mulheim | 2021/09/25 10:00 | Colin Sinclair v Weng, Jing Long | 6-1,6-4 |
| UTR Pro Tennis Series Mulheim | 2021/09/24 13:30 | Weng, Jing Long v Bielinskyi, Oleksandr | 1-6,6-3,1-6 |
| UTR Pro Tennis Series Mulheim | 2021/09/22 11:00 | Weng, Jing Long v Julien De Cuyper | 6-1,5-4 |
| UTR Pro Tennis Series Mulheim | 2021/09/20 11:00 | Carretero, Pablo v Weng, Jing Long | 2-6,6-3,6-6 |
| ITF M25 Eupen | 2021/09/06 09:15 | Jip Van Assendelft v Weng, Jing Long | 6-4,6-1 |
| UTR Pro Tennis Series Mulheim | 2021/10/14 10:00 | Dzhavakian, Yurii v Schmitz, Constantin | 4-6,5-7 |
| UTR Pro Tennis Series Mulheim | 2021/10/12 08:30 | Edison Ambarzumjan v Schmitz, Constantin | 2-6,2-5 |
| UTR Pro Tennis Series Mulheim | 2021/10/11 07:00 | Schmitz, Constantin v Sandkaulen, Tim | 6-4,7-5 |
| ITF M15 Allershausen | 2021/08/31 11:25 | Schmitz, Constantin v Veldheer, Mick | 6-7,4-6 |
| ITF M25 Trier | 2021/08/26 09:30 | Schmitz, Constantin v Ryan Nijboer | 4-6,2-6 |
| ITF M25 Trier | 2021/08/25 11:40 | Mats Rosenkranz v Schmitz, Constantin | 1-6,1-6 |
| ITF M15 Oldenzaal | 2021/08/19 12:35 | Schmitz, Constantin v Johnson, Luke | 7-5,0-6,3-6 |
| ITF M15 Oldenzaal | 2021/08/18 14:10 | Schmitz, Constantin v Eisinga, Zachary | 6-3,7-6 |