Stadium: Court 2 Round: 27 Ground: Clay
| Challenger Modena | 2023/06/27 19:40 | Lucas Gerch v Rodrigo Pacheco Mendez | 6-7,4-6 |
| Challenger Modena | 2023/06/26 08:00 | Timo Stodder v Lucas Gerch | 4-6,2-6 |
| Challenger Modena | 2023/06/25 08:00 | Gabriele Bosio v Lucas Gerch | 4-6,4-6 |
| Challenger Parma | 2023/06/18 14:00 | Lucas Gerch v Filippo Moroni | 6-1,1-6,4-6 |
| Challenger Heilbronn | 2023/06/06 12:55 | Maxime Janvier v Lucas Gerch | 6-4,6-3 |
| Challenger Heilbronn | 2023/06/05 11:00 | Lucas Gerch v Maxime Janvier | 6-2,6-2 |
| Challenger Heilbronn | 2023/06/04 15:15 | Lucas Gerch v Jose Pereira | 6-1,6-4 |
| ITF M15 Krsko | 2023/05/21 09:00 | Lucas Gerch v Mirza Basic | 6-4,6-1 |
| ITF M15 Cluj Napoca | 2023/06/22 06:50 | Johannes Haerteis v Gabi Adrian Boitan | 2-6,3-6 |
| ITF M15 Cluj Napoca | 2023/06/21 09:10 | Dan Alexandru Tomescu v Johannes Haerteis | 4-6,2-6 |
| ITF M15 Cluj Napoca | 2023/06/20 06:25 | Johannes Haerteis v Mihai Alexandru Coman | 6-4,7-6 |
| ITF M15 Vaasa | 2023/06/07 12:45 | Johannes Haerteis v Iiro Vasa | 4-6,1-6 |
| Challenger Prague Qual | 2023/05/07 12:55 | Vitaliy Sachko v Johannes Haerteis | 5-7,6-2,6-1 |
| ITF M25 Sanxenxo | 2023/04/28 13:00 | Robert Strombachs v Johannes Haerteis | 7-6,6-4 |
| ITF M25 Sanxenxo | 2023/04/27 12:30 | Johannes Haerteis v Tao Mu | 6-4,6-1 |
| ITF M25 Sanxenxo | 2023/04/26 10:00 | Johannes Haerteis v Grigory Kuklin | 6-1,6-0 |