Stadium: Court 2 Round: 19 Ground: Clay
| ITF Germany F16 | 2015/10/13 10:40 | David Poljak v Johannes Haerteis | 4-6,1-6 |
| Challenger Prostejov | 2021/06/13 09:00 | Johannes Haerteis v Jakub Nicod | 6-3,3-6,6-3 |
| Challenger Bratislava | 2021/06/06 14:15 | Skander Mansouri v Johannes Haerteis | 6-3,7-5 |
| Challenger Oeiras | 2021/05/25 14:00 | Johannes Haerteis v Filip Cristian Jianu | 3-6,0-6 |
| Challenger Ortisei | 2020/11/19 10:00 | Johannes Haerteis v Ilya Ivashka | 6-7,3-6 |
| Challenger Ortisei | 2020/11/17 09:00 | Daniel Masur v Johannes Haerteis | 3-6,7-6,3-6 |
| Challenger Ortisei | 2020/11/15 10:00 | Alexey Vatutin v Johannes Haerteis | 3-6,6-3,3-6 |
| Challenger Ortisei | 2020/11/14 09:00 | Johannes Haerteis v Viktor Galovic | 4-6,7-6,6-4 |
| Challenger Bratislava | 2020/11/08 11:00 | Johannes Haerteis v Julian Lenz | 7-6,4-6,6-7 |
| Challenger Prostejov | 2021/06/13 09:00 | David Poljak v Sem Verbeek | 6-3,6-3 |
| ITF M15 Monastir | 2021/05/25 08:30 | David Poljak v Naoki Nakagawa | 6-7,7-6,1-6 |
| ITF M15 Monastir | 2021/05/20 08:25 | David Poljak v Jeremy Beale | 6-7,1-6 |
| ITF M15 Monastir | 2021/05/18 10:20 | David Poljak v Louis Tessa | 7-6,6-4 |
| Challenger Salinas 2 | 2021/04/27 14:30 | Gonzalo Villanueva v David Poljak | 5-7,7-6,7-6 |
| Challenger Salinas 2 | 2021/04/26 18:35 | Miguel M Larrea v David Poljak | 3-6,0-6 |
| Challenger Salinas | 2021/04/18 15:00 | Tak Khunn Wang v David Poljak | 6-3,6-3 |
| ITF M15 Sharm El Sheikh | 2021/04/10 07:30 | Mukund Sasikumar v David Poljak | 6-3,6-2 |