| UTR Pro Tennis Series Mulheim | 2021/07/31 08:30 | Hazem Naw v Tim Sandkaulen | 6-4,7-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/29 13:30 | Matthew Thomson v Tim Sandkaulen | 6-7,1-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/29 07:00 | Billy Harris v Tim Sandkaulen | 6-7,3-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/28 11:00 | Mark Wallner v Tim Sandkaulen | 6-7,5-6 |
| UTR Pro Tennis Series Mulheim | 2021/07/26 11:00 | Guy Den Heijer v Tim Sandkaulen | 7-5,6-3 |
| Challenger Braunschweig | 2021/07/05 09:30 | Tim Sandkaulen v Daniel Michalski | 3-6,5-7 |
| Challenger Braunschweig | 2021/07/04 09:00 | Kacper Zuk v Tim Sandkaulen | 6-2,3-6,6-7 |
| ITF USA F25 | 2018/09/15 17:30 | Alan Kohen v Tim Sandkaulen | 6-4,6-4 |
| UTR Pro Tennis Series Mulheim | 2021/09/20 09:30 | Artem Podorozhnyi v Jurriaan Bol | 7-6,5-3 |
| ITF M15 Huy | 2021/08/22 15:50 | Thorsten Sollie v Jurriaan Bol | 3-6,6-2,10-2 |