| UTR Pro Tennis Series Sofia | 2021/09/01 08:00 | Christos Keisidis v Mario Radev | 6-1,4-6,6-4 |
| UTR Pro Tennis Series Sofia | 2021/08/31 08:00 | Denislav Prodanov v Mario Radev | 6-1,1-6,6-3 |
| UTR Pro Tennis Series Sofia | 2021/08/30 10:45 | Mario Radev v Josh Sheehy | 1-6,2-6 |
| UTR Pro Tennis Series Sofia | 2021/08/29 12:00 | George Lazarov v Mario Radev | 6-0,6-1 |