| UTR Pro Tennis Series Nis | 2021/10/06 11:30 | Aleksa Mardjonovic v George Botezan | 6-4,5-3 |
| UTR Pro Tennis Series Nis | 2021/10/05 14:00 | Aleksa Mardjonovic v Christos Keisidis | 2-6,7-5,6-4 |
| UTR Pro Tennis Series Nis | 2021/10/04 10:00 | Aleksa Mardjonovic v Dusan Trunic | 6-3,6-2 |
| ITF M15 Pirot | 2021/09/21 12:25 | Aleksa Mardjonovic v Kristijan Juhas | 2-6,4-6 |
| ITF M15 Pirot | 2021/09/20 11:00 | Paul Valsecchi v Aleksa Mardjonovic | 4-6,6-4,6-10 |
| ITF M15 Pirot | 2021/09/19 12:30 | Dusan Trunic v Aleksa Mardjonovic | 4-6,6-2,7-10 |
| ITF M15 Zlatibor | 2021/09/15 13:20 | Aleksa Mardjonovic v Petar Pjevcevic | 6-1,3-6,3-6 |
| ITF M15 Ulcinj | 2021/09/05 07:30 | Aleksa Mardjonovic v Alessandro Procopio | 7-6,4-6,6-10 |
| UTR Pro Tennis Series Nis | 2021/10/06 11:30 | Dusan Trunic v Alexander Lazov | 6-4,2-6,1-6 |
| UTR Pro Tennis Series Nis | 2021/10/04 11:30 | Christos Keisidis v Alexander Lazov | 6-3,0-6,3-6 |
| UTR Pro Tennis Series Ricany | 2021/09/18 09:00 | Antonin Bolardt v Alexander Lazov | 4-6,6-4,2-5 |
| UTR Pro Tennis Series Ricany | 2021/09/16 07:00 | Alexander Lazov v Jan Satral | 1-6,2-6 |
| UTR Pro Tennis Series Ricany | 2021/09/15 12:00 | Alexander Lazov v Yanais Laurent | 4-6,6-1,3-5 |
| UTR Pro Tennis Series Ricany | 2021/09/14 09:00 | Alexander Lazov v Yann Wojcik | 6-4,3-6,6-7 |
| UTR Pro Tennis Series Ricany | 2021/09/13 12:00 | Alexander Lazov v Michael Gloeckler | 6-3,6-3 |
| UTR Pro Tennis Series Sofia | 2021/09/04 07:30 | Alexander Lazov v George Lazarov | 3-5 |