Stadium: Center Round: 25 Ground: Clay
| ITF M25 - Quinta Do Lago | 2022/03/25 10:00 | Alec Deckers v Guy Den Ouden | 7-6,6-1 |
| ITF M15 - Alkmaar | 2023/06/30 14:30 | Alec Deckers v Luke Simkiss | 6-7,6-4,4-6 |
| ITF M15 - Alkmaar | 2023/06/29 16:55 | Alec Deckers v Michiel de Krom | 6-3,6-4 |
| ITF M15 - Alkmaar | 2023/06/28 09:00 | Alec Deckers v Paul Woerner | 6-4,6-2 |
| ATP Hertogenbosch | 2023/06/10 09:00 | David Goffin v Alec Deckers | 6-4,6-1 |
| ITF M15 - Warmbad-Villach | 2023/05/22 13:15 | Alec Deckers v Alex Barrena | 3-6,1-6 |
| ITF M25 - Nottingham | 2023/05/02 12:00 | Alec Deckers v Patrick Brady | 5-7,3-6 |
| ITF M25 - Nottingham | 2023/04/28 13:05 | Lucas Poullain v Alec Deckers | 6-4,6-7,6-3 |
| ITF M25 - Nottingham | 2023/04/28 11:30 | Lucas Poullain v Alec Deckers | 6-4,6-7,5-3 |
| ITF M15 - Alkmaar | 2023/06/29 12:05 | Jeffrey Von Der Schulenburg v Guy Den Ouden | 6-4,3-6,7-5 |
| ITF M15 - Alkmaar | 2023/06/28 11:30 | Deney Wassermann v Guy Den Ouden | 6-7,5-7 |
| ITF M25 - Risskov/Århus | 2023/06/17 09:00 | Guy Den Ouden v Leo Borg | 6-3,4-6,1-6 |
| ITF M25 - Risskov/Århus | 2023/06/16 09:55 | Max Houkes v Guy Den Ouden | 6-3,3-6,4-6 |
| ITF M25 - Risskov/Århus | 2023/06/15 08:30 | Philipp Pavlenko v Guy Den Ouden | 2-6,1-6 |
| ITF M25 - Risskov/Århus | 2023/06/14 08:25 | Carl Emil Overbeck v Guy Den Ouden | 1-6,2-6 |
| ITF M25 - Bodrum | 2023/05/25 07:00 | Valentin Vacherot v Guy Den Ouden | 6-3,6-3 |
| ITF M25 - Bodrum | 2023/05/24 07:00 | Guy Den Ouden v Egor Agafonov | 6-1,7-6 |