| ITF M15 Sozopol | 2021/10/05 13:30 | Sarp Agabigun v Gabriel Donev | 5-7,5-7 |
| ITF M15 Sozopol | 2021/09/15 08:30 | George Lazarov v Gabriel Donev | 6-1,6-3 |
| ITF M15 Ulcinj | 2021/09/10 09:00 | Gabriel Donev v Edoardo Lavagno | 1-6,2-6 |
| ITF M15 Ulcinj | 2021/09/09 09:50 | Aziz Kijametovic v Gabriel Donev | 5-7,6-7 |
| ITF M15 Ulcinj | 2021/09/08 08:00 | Gabriel Donev v Dusan Rajic | 6-4,6-7,7-5 |
| ITF M15 Ulcinj | 2021/09/03 08:55 | Gabriel Donev v Ignacio Carou | 4-6,3-6 |
| ITF M15 Ulcinj | 2021/09/02 08:30 | Gorazd Srbljak v Gabriel Donev | 1-6,6-7 |
| ITF M15 Telavi | 2021/08/04 08:45 | Evgeny Philippov v Gabriel Donev | 2-6,3-6 |
| UTR Pro Tennis Series Nis | 2021/10/10 08:00 | Oleksandr Bielinskyi v Egor Novikov | 6-2,5-3 |
| UTR Pro Tennis Series Nis | 2021/10/09 09:58 | Oleksandr Bielinskyi v George Botezan | 6-7,6-4,6-2 |
| UTR Pro Tennis Series Nis | 2021/10/08 16:45 | Lawrence Bataljin v Oleksandr Bielinskyi | 7-5,5-7,0-5 |
| UTR Pro Tennis Series Nis | 2021/10/07 07:00 | Ivan Liutarevich v Oleksandr Bielinskyi | 5-7,6-4,5-2 |
| UTR Pro Tennis Series Nis | 2021/10/06 08:30 | Stefan Ivic v Oleksandr Bielinskyi | 4-6,6-2,6-0 |
| UTR Pro Tennis Series Nis | 2021/10/04 08:30 | Veljko Krstic v Oleksandr Bielinskyi | 5-7,6-1,6-3 |
| UTR Pro Tennis Series Barcelona | 2021/09/27 12:30 | Oleksandr Bielinskyi v Noah Lopez | 6-3,4-5 |
| UTR Pro Tennis Series Mulheim | 2021/09/25 13:43 | Oleksandr Bielinskyi v Buvaysar Gadamauri | 6-7,6-7 |