Stadion: Court 6 Round: 25 Ground: Hardcourt outdoor
| ITF - M15 - Vyshkovo | 2021/09/21 07:00 | Szymon Kielan v Artem Smirnov | 6-4,3-6,3-6 |
| Challenger - Stettin | 2021/09/12 09:00 | Szymon Kielan v Alex Rybakov | 2-6,6-2,3-6 |
| Challenger - Warschau | 2021/08/26 13:00 | Lucas Miedler v Szymon Kielan | 7-5,6-4 |
| Challenger - Warschau | 2021/08/25 08:00 | Szymon Kielan v Goncalo Oliveira | 7-5,6-0 |
| ITF - M15 - Lodz | 2021/08/19 10:30 | Daniel Michalski v Szymon Kielan | 3-6,7-5,6-3 |
| ITF - M15 - Lodz | 2021/08/18 09:30 | Roman Andres Burruchaga v Szymon Kielan | 6-7,3-6 |
| ITF - M15 - Gdynia | 2021/08/12 10:25 | Szymon Kielan v Alexis Musialek | 3-6,4-6 |
| ITF - M15 - Gdynia | 2021/08/11 14:25 | Luke Johnson v Szymon Kielan | 1-6,6-7 |
| Davis Cup | 2021/09/19 08:45 | Alexandros Skorilas v Vilius Gaubas | 6-4,6-4 |
| ITF - M15 - Kairo | 2021/09/08 08:00 | Quentin Folliot v Alexandros Skorilas | 6-3,7-6 |
| ITF - M15 - Kairo | 2021/09/01 11:50 | Alexandros Skorilas v Sherif Makhlouf | 3-6,2-6 |
| ITF - M15 - Monastir | 2021/07/12 14:30 | Alexandros Skorilas v Perry Gregg | 0-6,3-6 |
| ITF - M15 - Monastir | 2021/07/12 09:00 | Alexandros Skorilas v Nicolas Hollender | 2-6,7-5,10-6 |
| ITF - M15 - Monastir | 2021/07/11 10:00 | Alexandros Skorilas v Skander Ben Abdallah | 6-3,6-3 |
| ITF - M15 - Monastir | 2021/07/04 11:00 | Alexandros Skorilas v Daniel Ibragimov | 6-7,2-6 |
| ITF - M15 - Heraklion | 2021/05/30 06:30 | Floris Podzimek v Alexandros Skorilas | 6-2,6-2 |