Stadium: Center Round: 24 Ground: Clay
| Challenger Sibiu | 2018/09/16 10:35 | Haerteis, Johannes v Lenz, Julian | 4-6,4-6 |
| ITF Switzerland F1 | 2018/02/06 12:00 | Haerteis, Johannes v Lenz, Julian | 6-2,1-6,4-6 |
| Czech Republic F2, Singles | 2017/05/27 11:55 | Lenz, Julian v Haerteis, Johannes | 6-1,6-4 |
| ITF Germany F10 | 2016/08/11 14:25 | Lenz, Julian v Haerteis, Johannes | 5-7,6-3,3-6 |
| Prostejov, Czech Republic | 2019/06/03 12:20 | de Greef, Arthur v Haerteis, Johannes | 4-6,4-6 |
| Prostejov, Czech Republic | 2019/06/02 14:40 | Benjamin Lock v Haerteis, Johannes | 6-2,2-6,3-6 |
| Jerusalem, Israel | 2019/05/20 07:00 | Haerteis, Johannes v Escobar, Gonzalo | 3-6,7-5,2-6 |
| Challenger - Rome | 2019/05/07 12:10 | Haerteis, Johannes v Stefano Napolitano | 2-6,3-6 |
| Challenger - Rome | 2019/05/06 10:00 | Skander Mansouri v Haerteis, Johannes | 6-7,7-6,5-7 |
| Challenger - Savannah | 2019/04/30 14:00 | Cannon Kingsley v Haerteis, Johannes | 6-2,6-2 |
| Challenger - Tallahassee | 2019/04/24 14:00 | Mitchell Krueger v Haerteis, Johannes | 3-6,6-4,6-1 |
| Challenger - Tallahassee | 2019/04/23 16:40 | Haerteis, Johannes v Song, Evan | 6-4,6-4 |
| Parma II, Italy | 2019/06/21 09:00 | Jacopo Berrettini v Lenz, Julian | 1-6,3-6 |
| Parma II, Italy | 2019/06/20 09:25 | Filip Peliwo v Lenz, Julian | 3-6,1-6 |
| Parma II, Italy | 2019/06/19 10:05 | Lenz, Julian v Alessandro Giannessi | 6-1,6-4 |
| Parma II, Italy | 2019/06/18 08:00 | Riccardo Bonadio v Lenz, Julian | 6-7,2-6 |
| Karlsruhe, Singles M-ITF-GER-04A | 2019/06/09 11:00 | Lenz, Julian v Andrea Pellegrino | 6-3,6-7,6-3 |
| Karlsruhe, Singles M-ITF-GER-04A | 2019/06/08 14:50 | Lenz, Julian v Netuschil, Marvin | 6-1,6-2 |
| Karlsruhe, Singles M-ITF-GER-04A | 2019/06/07 14:00 | Lenz, Julian v Gonzalo Villanueva | 6-3,6-0 |
| Karlsruhe, Singles M-ITF-GER-04A | 2019/06/06 11:30 | Lenz, Julian v Lindell, Christian | 6-3,6-3 |