Stadium: M (CC) Round: 25 Ground: Clay
| UTR Pro Tennis Series Mulheim | 2021/07/31 08:30 | Vasile Antonescu v Alexander Hoogmartens | 5-7,7-6,6-1 |
| UTR Pro Tennis Series Mulheim | 2021/07/30 13:30 | Guy Den Heijer v Alexander Hoogmartens | 6-2,3-6,4-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/30 07:00 | Francesco Vilardo v Alexander Hoogmartens | 1-6,2-5 |
| UTR Pro Tennis Series Mulheim | 2021/07/29 08:30 | Jim Hendrikx v Alexander Hoogmartens | 4-6,3-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/28 12:30 | Stefan Peter Hampe v Alexander Hoogmartens | 2-6,1-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/26 08:00 | Hazem Naw v Alexander Hoogmartens | 6-4,5-4 |
| ITF M15 Gaiba | 2021/06/09 16:15 | Alexander Hoogmartens v Federico Bertuccioli | 7-6,2-6,4-6 |
| ITF M15 Antalya | 2021/03/17 09:55 | Miljan Zekic v Alexander Hoogmartens | 5-7,7-5,6-2 |
| ITF M15 Esch/Alzette | 2021/07/22 13:05 | Deney Wassermann v Patrick Kypson | 2-6,3-6 |
| ITF M15 Esch/Alzette | 2021/07/21 11:10 | Wilson Leite v Deney Wassermann | 6-3,1-6,3-6 |
| ITF M15 Esch/Alzette | 2021/07/20 08:55 | Deney Wassermann v Luca Van Assche | 6-0,6-3 |
| ITF M15 Esch/Alzette | 2021/07/19 11:30 | Alexander Marinov v Deney Wassermann | 1-6,3-6 |
| ITF M15 Esch/Alzette | 2021/07/18 13:40 | Maksym Khalus v Deney Wassermann | 1-6,3-6 |
| Challenger Amersfoort | 2021/07/13 14:20 | Deney Wassermann v Kimmer Coppejans | 3-6,7-5,2-6 |
| Challenger Amersfoort | 2021/07/12 09:00 | Alvaro Lopez San Martin v Deney Wassermann | 4-6,4-6 |
| Challenger Amersfoort | 2021/07/11 11:40 | Deney Wassermann v Gauthier Onclin | 7-5,6-3 |