Stadium: Court 2 Kuhstall Round: 25 Ground: Clay
| ITF M25 - Ystad | 2023/08/16 08:45 | Valentin Vacherot v Johannes Haerteis | 6-2,6-7,6-4 |
| ITF M15 - Frankfurt Am Main | 2023/08/11 12:50 | Lucas Gerch v Johannes Haerteis | 7-5,6-0 |
| ITF M15 - Frankfurt Am Main | 2023/08/10 10:55 | Kai Lemstra v Johannes Haerteis | 7-5,4-6,2-6 |
| Challenger - Porto | 2023/08/01 16:10 | Johannes Haerteis v Emilio Nava | 6-7,6-7 |
| Challenger - Porto | 2023/07/31 10:00 | Hugo Maia v Johannes Haerteis | 5-7,5-7 |
| Challenger - Porto | 2023/07/30 10:00 | Johannes Haerteis v Victor Lilov | 6-4,2-6,6-2 |
| ITF M25 - Porto | 2023/07/27 11:45 | Johannes Haerteis v Joao Domingues | 6-2,6-7,2-6 |
| ITF M25 - Porto | 2023/07/26 11:35 | Tomas Pinho v Johannes Haerteis | 4-6,6-7 |
| ITF M15 - Allershausen | 2023/08/30 08:00 | Luca Hesselmann v Serafin Zund | 6-2,6-1 |
| ITF M15 - Huy | 2023/08/21 17:45 | Roland Stuurman v Luca Hesselmann | 6-4,7-6 |
| ITF M15 - Huy | 2023/08/21 13:05 | Noah Thurner v Luca Hesselmann | 6-7,4-6 |
| ITF M15 - Kottingbrunn | 2023/08/14 08:00 | Luca Parenti v Luca Hesselmann | 6-3,6-7,10-8 |
| ITF M15 - Frankfurt Am Main | 2023/08/07 13:00 | Michael Agwi v Luca Hesselmann | 6-1,6-2 |
| ITF M15 - Frankfurt Am Main | 2023/08/07 08:00 | Essa Qabazard v Luca Hesselmann | 4-6,0-6 |
| ITF M15 - Uslar | 2023/07/17 08:00 | Torben Steinorth v Luca Hesselmann | 1-6,6-1,10-8 |
| ITF M25 - Kassel | 2023/07/10 09:20 | Luca Matteo Sobbe v Luca Hesselmann | 6-0,6-4 |