| 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 Barcelona | 2021/11/27 08:00 | David Redondo v Fermin Calvo Barcelo | 1-6,3-5 |
| UTR Pro Tennis Series Barcelona | 2021/11/26 13:00 | David Redondo v Stefanos Sakellaridis | 7-6,4-6,5-7 |
| UTR Pro Tennis Series Barcelona | 2021/11/25 15:45 | David Redondo v Diego Barreto | 3-6,2-6 |
| UTR Pro Tennis Series Barcelona | 2021/11/23 10:30 | David Redondo v Sergio Davila Godoy | 4-6,4-5 |
| UTR Pro Tennis Series Barcelona | 2021/11/22 09:30 | Saba Purtseladze v David Redondo | 6-3,3-6,4-6 |
| UTR Pro Tennis Series Barcelona | 2021/11/08 08:00 | David Redondo v Vlad Cristian Breazu | 5-7,4-5 |
| UTR Pro Tennis Series Barcelona | 2021/06/13 07:00 | Bruno P Navarro v David Redondo | 6-0,6-2 |
| UTR Pro Tennis Series Barcelona | 2021/06/11 09:30 | Jorge Martinez Martinez v David Redondo | 6-1,6-1 |