| UTR Pro Tennis Series - Nis | 2021/10/09 14:15 | Denys Klok v Lazar Radenkovic | 1-6,3-5 |
| UTR Pro Tennis Series - Nis | 2021/10/08 14:15 | Petar Teodorovic v Denys Klok | 7-5,6-0 |
| UTR Pro Tennis Series - Nis | 2021/10/07 07:00 | Egor Novikov v Denys Klok | 6-4,6-3 |
| UTR Pro Tennis Series - Nis | 2021/10/05 07:30 | Aleksandar Ljubojevic v Denys Klok | 6-3,3-6,0-6 |
| UTR Pro Tennis Series - Nis | 2021/10/04 07:00 | Denys Klok v Andrey Chepelev | 3-6,1-6 |