Stadium: Court 9 Round: 25 Ground: Clay
| ITF M15 Trnava | 2020/02/24 14:00 | Jiri Barnat v Piotr Grynkowski | 3-6,2-6 |
| ITF M15 Milovice | 2019/11/12 10:30 | Piotr Grynkowski v Jiri Barnat | 6-4,6-4 |
| ITF M25 Lodz | 2023/08/08 11:05 | Piotr Grynkowski v Piotr Siekanowicz | 6-4,6-1 |
| ITF M25 Lodz | 2023/08/07 10:30 | Siim Troost v Piotr Grynkowski | 6-7,6-7 |
| ITF M25 Jablonec Nad Nisou | 2023/05/29 10:30 | Thijmen Loof v Piotr Grynkowski | 7-6,7-5 |
| ITF M15 Lodz | 2022/07/27 13:30 | Piotr Grynkowski v Petr Nouza | 1-6,3-6 |
| ITF M15 Lodz | 2022/07/26 13:30 | Federico Campana v Piotr Grynkowski | 3-6,4-6 |
| ITF M15 Cairo | 2022/01/12 08:00 | Daniel Michalski v Piotr Grynkowski | 6-1,6-1 |
| ITF M15 Cairo | 2022/01/06 08:00 | Piotr Grynkowski v Simone Roncalli | 4-6,1-6 |
| ITF M15 Cairo | 2022/01/05 07:30 | Piotr Grynkowski v Preston Brown | 5-7,6-4,6-2 |
| Challenger Liberec | 2023/07/31 09:45 | Federico Agustin Gomez v Jiri Barnat | 1-6,6-3,7-6 |
| ITF M25 Kassel | 2023/07/13 09:30 | Hady Habib v Jiri Barnat | 6-2,6-3 |
| ITF M25 Kassel | 2023/07/11 13:00 | Jiri Barnat v Gilles Arnaud Bailly | 6-3,6-2 |
| ITF M15 Wroclaw | 2023/07/02 10:55 | Goncalo Oliveira v Jiri Barnat | 6-2,6-4 |
| ITF M15 Wroclaw | 2023/06/30 08:30 | Peter Benjamin Privara v Jiri Barnat | 4-6,2-6 |
| ITF M15 Wroclaw | 2023/06/29 07:50 | Nikita Mashtakov v Jiri Barnat | 3-6,6-4,4-6 |
| ITF M15 Wroclaw | 2023/06/27 09:40 | Gabriel Matuszewski v Jiri Barnat | 2-6,2-6 |
| ITF M25 Poprad | 2023/06/22 10:50 | Jiri Barnat v Patrik Rikl | 2-6,2-6 |