Stadium: Court 2 Round: 27 Ground: Hardcourt outdoor
| ITF M25 Sanxenxo | 2023/04/27 16:10 | Robert Strombachs v Julio Cesar Porras | 6-2,6-2 |
| ITF M25 Sanxenxo | 2023/04/26 16:00 | Robert Strombachs v Ander Tarrio Ponte | 6-1,6-1 |
| Challenger - Morelos | 2023/04/17 18:55 | Luke Saville v Robert Strombachs | 6-1,7-6 |
| Challenger Leon | 2023/04/09 18:50 | Robert Strombachs v Aidan Mchugh | 2-6,6-1,6-7 |
| Challenger - San Luis Potosí | 2023/04/02 19:35 | Panta Herreros, Jorge Brian v Robert Strombachs | 6-4,6-3 |
| ITF - M15 Sharm El Sheikh | 2023/03/18 08:00 | Lukas Pokorny v Robert Strombachs | 6-3,3-6,6-3 |
| ITF - M15 Sharm El Sheikh | 2023/03/17 08:00 | Robert Strombachs v Jakob Schnaitter | 6-2,6-1 |
| ITF - M15 Sharm El Sheikh | 2023/03/16 08:00 | Robert Strombachs v Zach Stephens | 6-1,7-5 |
| ITF M25 Sanxenxo | 2023/04/27 12:30 | Haerteis, Johannes v Tao Mu | 6-4,6-1 |
| ITF M25 Sanxenxo | 2023/04/26 10:00 | Haerteis, Johannes v Grigory Kuklin | 6-1,6-0 |
| ITF - M15 Antalya | 2023/04/21 07:30 | Madaras, Dragos Nicolae v Haerteis, Johannes | 6-2,6-2 |
| ITF - M15 Antalya | 2023/04/20 07:00 | Dan Alexandru Tomescu v Haerteis, Johannes | 1-6,6-4,2-6 |
| ITF - M15 Antalya | 2023/04/18 09:50 | Haerteis, Johannes v Arthur Reymond | 6-4,6-2 |
| ITF - M15 Antalya | 2023/04/12 07:00 | Capecchi, Daniele v Haerteis, Johannes | 4-6,6-3,6-2 |
| ITF - M25 Trente | 2023/03/30 15:00 | Giovanni Oradini v Haerteis, Johannes | 6-4,6-0 |
| ITF - M25 Trente | 2023/03/29 07:30 | Bulitski, Aliaksandr v Haerteis, Johannes | 2-6,2-6 |