Stadium: Main Court (7) Round: 44 Ground: Clay
| Polish National Tour | 2021/07/13 10:35 | Piotr Matuszewski v Wojciech Marek | 6-4,6-3 |
| ITF M25 Casinalbo | 2021/07/05 07:30 | Piotr Matuszewski v Gabriel Roveri Sidney | 6-2,4-6,6-10 |
| ITF M25 Casinalbo | 2021/07/04 08:45 | Piotr Matuszewski v Lorenzo Favero | 6-4,6-4 |
| ITF M25 Most | 2021/05/25 08:00 | Piotr Matuszewski v Hasan Ibrahim | 6-2,2-6,9-11 |
| ITF M25 Most | 2021/05/24 08:00 | Piotr Matuszewski v Theo Arribage | 7-5,7-5 |
| ITF M25 Most | 2021/05/23 08:00 | Piotr Matuszewski v Michal Novansky | 6-4,1-6,12-10 |
| ITF M25 Prague | 2021/05/09 07:30 | Pavel Nejedly v Piotr Matuszewski | 7-5,6-4 |
| ITF M15 Monastir | 2021/04/12 12:30 | Piotr Matuszewski v Sean Hodkin | 1-6,0-6 |
| ITF M25 Grodzisk Mazowiecki | 2021/08/01 13:55 | Simon Sedliak v Peter Samosi | 6-2,7-5 |
| ITF M15 Poprad | 2021/07/04 11:00 | Dominik Palan v Simon Sedliak | 6-3,6-1 |
| ITF M15 Novomoskovsk | 2021/05/31 06:15 | Aleksandr Braynin v Simon Sedliak | 7-6,6-1 |
| ITF M15 Novomoskovsk | 2021/05/30 06:15 | Philipp Sikorski v Simon Sedliak | 1-6,6-7 |
| ITF M15 Monastir | 2021/04/19 11:00 | Filip Bergevi v Simon Sedliak | 6-1,6-2 |
| ITF M15 Monastir | 2021/04/18 10:00 | Simon Sedliak v Andrej Krajcik | 6-1,6-0 |
| ITF M15 Monastir | 2021/04/11 09:00 | Simon Sedliak v Jonas Maier | 2-6,4-6 |