Stadium: Court 14 Round: 44 Ground: Hardcourt outdoor
| ITF M15 Heraklion | 2023/10/19 08:45 | Guy Den Heijer v Gabriel Decamps | 2-6,4-6 |
| ITF M25 Santa Margherita | 2023/09/25 08:00 | Niels Visker v Guy Den Heijer | 5-7,6-4,11-9 |
| ITF M25 Santa Margherita | 2023/09/24 08:00 | Niccolo Ciavarella v Guy Den Heijer | 6-2,3-6,7-10 |
| ITF M25 Santa Margherita | 2023/09/18 08:30 | Guy Den Heijer v Toby Martin | 5-7,6-3,7-10 |
| ITF M15 Haren | 2023/09/07 17:25 | Guy Den Heijer v Adrian Oetzbach | 6-7,6-7 |
| ITF M15 Haren | 2023/09/05 17:30 | Guy Den Heijer v Kjell De Hek | 6-3,6-1 |
| ITF M25 Oldenzaal | 2023/08/30 18:10 | Aleksandr Braynin v Guy Den Heijer | 4-6,7-6,7-5 |
| ITF M25 Lesa | 2023/08/24 18:45 | Clement Tabur v Guy Den Heijer | 6-1,6-4 |
| ITF M15 Heraklion | 2023/10/22 09:30 | Piotr Kusiewicz v Vojtech Mares | 5-7,6-4,7-10 |
| ITF M25 Pardubice | 2023/09/18 09:00 | Vojtech Mares v Petr Michnev | 6-7,6-2,6-10 |
| ITF M25 Pardubice | 2023/09/17 08:00 | Jan Jermar v Vojtech Mares | 3-6,4-6 |
| ITF M25 Jablonec Nad Nisou | 2023/08/30 09:30 | Martin Krumich v Vojtech Mares | 3-6,6-4,6-4 |
| ITF M25 Jablonec Nad Nisou | 2023/08/29 10:30 | Vojtech Mares v Henry Lieberman | 6-7,6-4,10-5 |
| ITF M25 Lodz | 2023/08/09 08:00 | Vojtech Mares v Filip Pieczonka | 3-6,1-6 |
| ITF M25 Lodz | 2023/08/08 12:05 | Vojtech Mares v Tomas Vaise | 3-6,7-6,10-8 |
| ITF M25 Lodz | 2023/08/08 07:30 | Edison Ambarzumjan v Vojtech Mares | 4-6,1-6 |