| UTR Pro Tennis Series - Mulheim | 2021/09/20 12:30 | Guy Den Heijer v Lawrence Bataljin | 6-0,5-1 |
| UTR Pro Tennis Series - Amsterdam | 2021/11/02 10:30 | Guy Den Heijer v Jip Van Assendelft | 6-4,5-2 |
| UTR Pro Tennis Series - Amsterdam | 2021/11/01 13:30 | Miko Wassermann v Guy Den Heijer | 2-6,5-7 |
| ITF M15 - Girona | 2021/10/19 08:00 | Guy Den Heijer v Vladislav Ivanov | 6-4,6-3 |
| ITF M15 - Girona | 2021/10/18 08:00 | Guy Den Heijer v Samir Hamza Reguig | 6-2,6-1 |
| ITF M15 - Girona | 2021/10/17 08:00 | Guy Den Heijer v Ervin H Eminefendic | 6-3,6-1 |
| ITF M15 - Platja D'Aro | 2021/10/14 14:15 | Jose Fco. Vidal Azorin v Guy Den Heijer | 7-6,1-6,6-2 |
| ITF M15 - Platja D'Aro | 2021/10/13 12:00 | Guy Den Heijer v Fermin Tenti | 6-4,3-6,6-1 |
| ITF M15 - Platja D'Aro | 2021/10/12 08:30 | Guy Den Heijer v Marc Othman Ktiri | 6-4,6-2 |
| UTR Pro Tennis Series - Amsterdam | 2021/11/01 13:30 | Johann Willems v Lawrence Bataljin | 6-1,5-1 |
| UTR Pro Tennis Series - Mulheim | 2021/10/12 07:00 | Eric Vanshelboim v Lawrence Bataljin | 6-1,5-3 |
| UTR Pro Tennis Series - Nis | 2021/10/09 11:00 | Christos Keisidis v Lawrence Bataljin | 6-4,6-2 |
| UTR Pro Tennis Series - Nis | 2021/10/08 16:45 | Lawrence Bataljin v Oleksandr Bielinskyi | 7-5,5-7,0-5 |
| UTR Pro Tennis Series - Nis | 2021/10/07 08:30 | Lawrence Bataljin v Veljko Krstic | 7-6,3-6,5-7 |
| UTR Pro Tennis Series - Nis | 2021/10/06 08:30 | Ivan Liutarevich v Lawrence Bataljin | 7-5,6-3 |
| UTR Pro Tennis Series - Nis | 2021/10/05 09:00 | Stefan Ivic v Lawrence Bataljin | 4-6,4-5 |
| UTR Pro Tennis Series - Zadar | 2021/10/03 08:00 | Duje Kekez v Lawrence Bataljin | 6-1,5-1 |