Stadion: Court 3 Round: 26 Ground: Clay
| ITF - M15 - Oldenzaal | 2021/08/18 14:30 | Kai Wehnelt v Daniel De Jonge | 5-7,6-1,6-7 |
| ITF - M15 - Gdynia | 2021/08/13 09:00 | Roman Andres Burruchaga v Daniel De Jonge | 7-6,6-1 |
| ITF - M15 - Gdynia | 2021/08/12 09:25 | Gilbert S K Junior v Daniel De Jonge | 5-7,1-6 |
| ITF - M15 - Gdynia | 2021/08/11 08:00 | Daniel De Jonge v Markus Eriksson | 6-4,6-1 |
| ITF - M15 - Gdynia | 2021/08/10 08:00 | Juliusz Bienkiewicz v Daniel De Jonge | 2-6,6-7 |
| ITF - M15 - Gdynia | 2021/08/09 08:00 | Sergo Sikharulidze v Daniel De Jonge | 3-6,2-6 |
| ITF - M15 - Gdynia | 2021/08/08 08:00 | Valerio Aboian v Daniel De Jonge | 5-7,6-7 |
| ITF - M15 - Frederiksberg | 2021/08/05 10:25 | Christian Sigsgaard v Daniel De Jonge | 6-4,7-6 |
| ITF - M15 - Oldenzaal | 2021/08/18 15:00 | Petros Tsitsipas v Gabriel Alejandro Hidalgo | 7-5,6-2 |
| Challenger - Meerbusch | 2021/08/08 12:05 | Nerman Fatic v Petros Tsitsipas | 6-1,7-6 |
| ITF - M25 - Bozen | 2021/08/04 08:25 | Petros Tsitsipas v Andrea Gola | 2-6,2-6 |
| ITF - M25 - Bozen | 2021/08/03 15:35 | Petros Tsitsipas v Jonas Greif | 6-3,6-2 |
| ITF - M25 - Kottingbrunn | 2021/07/19 09:30 | Petros Tsitsipas v Raffael Schaer | 3-6,4-6 |
| ITF - M25 - Kottingbrunn | 2021/07/18 07:30 | Petros Tsitsipas v Stephanos Schinas | 6-3,6-2 |
| ITF - M25 - Ajaccio | 2021/07/11 16:00 | Petros Tsitsipas v Clement Chidekh | 3-6,0-6 |
| ITF - M25 - Ajaccio | 2021/07/10 19:20 | Petros Tsitsipas v Loris Pourroy | 6-4,6-7,6-3 |