Stadium: Court 2 Round: 25 Ground: Clay
| Challenger Warsaw | 2021/08/22 09:00 | Wojciech Marek v Daniel Michalski | 6-7,1-6 |
| ITF M15 Lodz | 2021/08/20 08:00 | Yann Wojcik v Wojciech Marek | 7-6,6-3 |
| ITF M15 Lodz | 2021/08/19 07:55 | Wojciech Marek v Markus Eriksson | 6-4,7-5 |
| ITF M15 Lodz | 2021/08/18 11:25 | Wojciech Marek v Olaf Pieczkowski | 5-7,6-4,6-1 |
| ITF M15 Gdynia | 2021/08/12 08:00 | Alejo Lorenzo Lingua Lavallen v Wojciech Marek | 3-6,6-3,6-3 |
| ITF M15 Gdynia | 2021/08/10 14:30 | Wojciech Marek v Georgii Kravchenko | 6-4,6-2 |
| Challenger Poznan | 2021/07/25 11:00 | Joao Domingues v Wojciech Marek | 6-3,6-0 |
| Polish National Tour | 2021/07/13 10:35 | Piotr Matuszewski v Wojciech Marek | 6-4,6-3 |
| ITF M15 Bratislava | 2021/08/25 10:20 | Mariano Navone v Andrej Krajcik | 6-2,6-0 |
| ITF M15 Bratislava | 2021/08/18 08:00 | Frane Nincevic v Andrej Krajcik | 6-3,6-4 |
| ITF M15 Novi Sad | 2021/08/01 12:45 | Andrej Krajcik v Eric Morris | 1-6,6-1,8-10 |
| ITF M15 Novi Sad | 2021/07/25 08:15 | Matic Dimic v Andrej Krajcik | 6-4,5-7,10-8 |
| ITF M15 Poprad | 2021/07/04 08:00 | Andrej Krajcik v Caspar Schuetze | 1-6,2-6 |
| ITF M15 Antalya | 2021/06/20 07:00 | Sergo Sikharulidze v Andrej Krajcik | 4-6,6-3,10-6 |
| ITF M15 Monastir | 2021/04/18 10:00 | Simon Sedliak v Andrej Krajcik | 6-1,6-0 |
| ITF M15 Monastir | 2021/04/11 10:00 | Igor Marcondes v Andrej Krajcik | 6-2,6-3 |