Stadium: Lear Round: 26 Ground: Clay
| ITF M15 Allershausen | 2023/08/30 12:00 | Mark Wallner v Lawrence Sciglitano | 6-3,6-2 |
| ITF M15 Allershausen | 2023/08/30 08:00 | Karlo Cubelic v Mark Wallner | 6-3,2-6,7-10 |
| ITF M15 Überlingen | 2023/08/17 08:00 | Mark Wallner v Fnu Nidunjianzan | 4-6,6-4,3-6 |
| ITF M15 Überlingen | 2023/08/16 08:00 | Gregor Ramskogler v Mark Wallner | 3-6,2-6 |
| ITF M15 Überlingen | 2023/08/14 08:00 | Daniel L Salmeron v Mark Wallner | 1-6,6-7 |
| ITF M15 Frankfurt Nad Mohanem | 2023/08/07 16:00 | Gregor Ramskogler v Mark Wallner | 6-4,7-5 |
| ITF M15 Frankfurt Nad Mohanem | 2023/08/07 10:00 | Mark Wallner v Giuseppe La Vela | 6-4,7-5 |
| ITF M15 Celje | 2023/06/27 07:00 | Gian Marco Ortenzi v Mark Wallner | 6-4,6-4 |
| ITF M15 Allershausen | 2023/08/30 10:00 | Daniel De Jonge v Dominik Boehler | 6-4,7-6 |
| ITF M15 Huy | 2023/08/24 09:00 | Buvaysar Gadamauri v Daniel De Jonge | 6-4,6-3 |
| ITF M15 Huy | 2023/08/23 09:00 | Daniel De Jonge v Noah Merre | 1-6,6-2,6-0 |
| ITF M15 Huy | 2023/08/21 15:20 | Daniel De Jonge v Ruben Hartig | 6-3,5-7,5-10 |
| ITF M25 Koksijde | 2023/08/13 12:15 | Daniel De Jonge v Mats Bredschneijder | 4-6,6-1,5-10 |
| ITF M15 Eindhoven | 2023/08/01 11:35 | Daniel De Jonge v Maxime Mora | 6-1,5-7,1-6 |
| ITF M15 Eindhoven | 2023/07/31 08:00 | Guy Den Heijer v Daniel De Jonge | 6-7,7-5,11-13 |
| ITF M15 Eindhoven | 2023/07/30 09:30 | Luca Matteo Sobbe v Daniel De Jonge | 4-6,3-6 |