Stadium: Center Court Round: 26 Ground: Carpet indoor
| Challenger - Barcelone | 2018/10/08 12:05 | Wang, Tak Khunn v Jahn, Jeremy | 6-4,6-4 |
| Challenger - Barcelone | 2018/10/07 15:10 | Jahn, Jeremy v Zizou Bergs | 7-6,6-1 |
| Challenger - Barcelone | 2018/10/07 07:15 | Nerman Fatic v Jahn, Jeremy | 2-6,6-4,1-6 |
| Florence, Italy | 2018/09/29 13:45 | Jahn, Jeremy v Nicola Kuhn | 3-6,6-3,4-6 |
| Challenger Sibiu | 2018/09/18 10:00 | Bolelli, Simone v Jahn, Jeremy | 6-4,6-4 |
| Challenger Sibiu | 2018/09/17 08:00 | Javier Barranco Cosano v Jahn, Jeremy | 1-6,4-6 |
| Challenger Sibiu | 2018/09/16 07:00 | Mircea-Alexandru Jecan v Jahn, Jeremy | 3-6,1-6 |
| Challenger Mallorca | 2018/08/26 09:50 | Joao Menezes v Jahn, Jeremy | 6-3,6-4 |
| Challenger Ismaning | 2018/10/16 13:25 | Louis Wessels v Lucas Miedler | 7-6,6-3 |
| ITF Germany F15 | 2018/10/11 13:30 | Louis Wessels v Ehrat, Sandro | 3-6,5-7 |
| ITF Germany F15 | 2018/10/10 14:40 | Louis Wessels v Hirschmueller, Christian | 2-6,6-2,7-6 |
| ITF Germany F14 | 2018/10/03 15:50 | Louis Wessels v Kai Lemstra | 6-7,6-1,4-6 |
| ITF Italy F28 | 2018/09/18 15:25 | Louis Wessels v Federico Iannaccone | 2-6,5-7 |
| ITF Italy F27 | 2018/09/15 12:00 | Bortolotti, Marco v Louis Wessels | 3-6,7-5,1-6 |
| ITF Italy F27 | 2018/09/14 13:00 | Louis Wessels v Riccardo Bonadio | 2-6,6-3,6-2 |
| ITF Italy F27 | 2018/09/13 14:30 | Alessandro Ingarao v Louis Wessels | 1-6,1-6 |