| UTR Pro Tennis Series Ricany | 2021/09/11 10:30 | Dominik Kellovsky v Stefanos Sakellaridis | 7-5,5-1 |
| UTR Pro Tennis Series Ricany | 2021/09/09 07:30 | Dominik Suc v Stefanos Sakellaridis | 5-7,6-7 |
| UTR Pro Tennis Series Ricany | 2021/09/07 09:00 | Filip Duda v Stefanos Sakellaridis | 4-6,6-4,5-2 |
| ITF M15 Bad Waltersdorf | 2021/08/31 07:00 | Luigi Sorrentino v Stefanos Sakellaridis | 6-0,5-7,10-7 |
| ITF M15 Bad Waltersdorf | 2021/08/22 09:00 | Joshua Peck v Stefanos Sakellaridis | 1-6,6-3,11-9 |
| ITF M15 Warmbad-Villach | 2021/08/17 07:30 | Lorenzo Vatteroni v Stefanos Sakellaridis | 7-6,6-2 |
| ITF M15 Warmbad-Villach | 2021/08/16 12:30 | Leon Benedict v Stefanos Sakellaridis | 4-6,3-6 |
| ITF M15 Novi Sad | 2021/08/01 14:00 | Stefanos Sakellaridis v Lukas Palovic | 4-6,1-6 |
| UTR Pro Tennis Series Ricany | 2021/09/16 07:00 | Antonin Bolardt v Petr Hajek | 2-6,1-6 |
| UTR Pro Tennis Series Ricany | 2021/09/15 12:00 | Dominik Recek v Petr Hajek | 7-6,5-3 |
| UTR Pro Tennis Series Ricany | 2021/09/13 07:30 | Matyas Cerny v Petr Hajek | 1-6,2-6 |
| ITF M15 Bad Waltersdorf | 2021/08/22 09:00 | Petr Hajek v Gabriel Decamps | 6-7,2-6 |
| ITF M15 Warmbad-Villach | 2021/08/18 08:00 | Petr Hajek v Tom Kocevar-Desman | 4-6,7-5,4-6 |
| ITF M15 Warmbad-Villach | 2021/08/17 08:00 | Petr Hajek v Ioannis Xilas | 6-3,7-6 |
| ITF M15 Warmbad-Villach | 2021/08/16 12:30 | Petr Hajek v Daniele Valentino | 6-3,6-1 |
| ITF M15 Gdynia | 2021/08/12 08:00 | Filip Peliwo v Petr Hajek | 6-1,6-3 |