Stadium: Court 5 Round: 26 Ground: Clay
| ITF M15 Novi Sad | 2021/07/28 11:10 | Ivan Nedelko v Gabriel Donev | 4-6,1-6 |
| ITF M15 Novi Sad | 2021/07/26 09:00 | Gabriel Donev v Dusan Rajic | 6-2,6-2 |
| ITF M15 Novi Sad | 2021/07/25 12:00 | Gabriel Donev v Besir Durguti | 6-1,6-1 |
| ITF M15 Sofia | 2021/07/09 08:30 | Gabriel Donev v Alexander Weis | 6-4,3-6,6-7 |
| ITF M15 Sofia | 2021/07/08 11:40 | Simeon Terziev v Gabriel Donev | 1-6,6-4,0-6 |
| ITF M15 Sofia | 2021/07/07 08:50 | Mattia Frinzi v Gabriel Donev | 5-7,2-6 |
| ITF M15 Novomoskovsk | 2021/06/03 11:45 | Alexander Zgirovsky v Gabriel Donev | 6-2,3-6,10-8 |
| ITF M15 Novomoskovsk | 2021/05/31 06:15 | Gabriel Donev v Denis Parshutin | 6-0,6-4 |
| ITF M15 Novi Sad | 2021/07/28 07:30 | Gorazd Srbljak v Marsel Ilhan | 6-2,6-4 |
| ITF M15 Novi Sad | 2021/07/27 07:30 | Danilo Raicevic v Gorazd Srbljak | 1-6,2-6 |
| ITF M15 Novi Sad | 2021/07/26 07:30 | Nemanja Malesevic v Gorazd Srbljak | 1-6,1-6 |
| ITF M15 Novi Sad | 2021/07/25 09:30 | Marc Othman Ktiri v Gorazd Srbljak | 4-6,1-6 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/17 07:00 | Gorazd Srbljak v Olexiy Kolisnyk | 0-6,6-4,3-6 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/16 06:00 | Gorazd Srbljak v Aleksandr Braynin | 6-4,3-6,6-3 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/15 09:00 | Gorazd Srbljak v Yanaki Milev | 6-3,6-2 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/14 07:30 | Vladimir Popov v Gorazd Srbljak | 1-6,4-6 |