Stadium: Center Court Round: 14 Ground: Clay
| 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 Eckental | 2020/11/04 12:55 | Sebastian Korda v Johannes Haerteis | 6-2,1-6,6-1 |
| ITF M25 Most | 2021/05/24 09:00 | Filip Duda v Jakub Nicod | 6-3,6-1 |