| Polish National Tour | 2020/06/17 07:00 | Piotr Grynkowski v Aleksander Orlikowski | 7-5,6-1 |
| ITF M15 Trnava | 2020/02/26 12:50 | Piotr Grynkowski v Jan Satral | 4-6,2-6 |
| ITF M15 Trnava | 2020/02/25 09:00 | Isa Mammetgulyyev v Piotr Grynkowski | 3-6,2-6 |
| ITF M15 Trnava | 2020/02/24 14:00 | Jiri Barnat v Piotr Grynkowski | 3-6,2-6 |
| ITF M15 Sharm El Sheikh | 2020/02/19 15:40 | Issei Okamura v Piotr Grynkowski | 6-3,7-5 |
| ITF M15 Sharm El Sheikh | 2020/02/18 09:30 | Piotr Grynkowski v Iancu-Iustinian Ghinda | 6-2,6-3 |
| ITF M15 Sharm El Sheikh | 2020/02/17 09:00 | Piotr Grynkowski v Ken Onishi | 6-1,6-4 |
| ITF M15 Sharm El Sheikh | 2020/02/12 08:00 | Pablo Vivero Gonzalez v Piotr Grynkowski | 6-3,6-3 |
| Marbello Cup Exhibition Series | 2020/06/05 08:20 | Filip Kolasinski v Jan Zielinski | 0-6,7-5,7-10 |
| Marbello Cup Exhibition Series | 2020/06/04 14:10 | Maciej Rajski v Jan Zielinski | 7-5,6-1 |
| Marbello Cup Exhibition Series | 2020/06/04 08:20 | Filip Kolasinski v Jan Zielinski | 6-7,4-6 |
| Marbello Cup Exhibition Series | 2020/06/03 14:40 | Maciej Rajski v Jan Zielinski | 4-6,4-6 |
| Marbello Cup Exhibition Series | 2020/06/03 08:50 | Jan Zielinski v Michal Dembek | 7-6,5-7,10-4 |
| Marbello Cup Exhibition Series | 2020/06/02 13:30 | Daniel Michalski v Jan Zielinski | 6-0,5-7,8-10 |
| Marbello Cup Exhibition Series | 2020/06/02 07:00 | Jan Zielinski v Mateusz Terczynski | 4-6,6-3,10-6 |
| ITF M25 Sunderland | 2020/02/24 11:40 | Jan Zielinski v George Houghton | 4-6,6-3,7-10 |