Stadium: Court 10 Round: 26 Ground: Clay
| ITF M15 Gdynia | 2021/08/11 09:40 | Antonin Bolardt v Gilbert S K Junior | 6-2,1-6,2-6 |
| ITF M25 Grodzisk Mazowiecki | 2021/08/07 07:00 | Gilbert S K Junior v Toby Alex Kodat | 6-1,6-7,3-6 |
| ITF M25 Grodzisk Mazowiecki | 2021/08/05 08:30 | Filip Peliwo v Gilbert S K Junior | 3-6,5-7 |
| ITF M15 Castelo Branco | 2021/08/01 09:00 | Clement Chidekh v Gilbert S K Junior | 2-6,1-6 |
| ITF M15 Castelo Branco | 2021/07/31 08:30 | Joao Lucas Reis da Silva v Gilbert S K Junior | 6-4,2-6,6-7 |
| ITF M15 Castelo Branco | 2021/07/30 10:00 | Gilbert S K Junior v Sho Shimabukuro | 7-6,6-3 |
| ITF M15 Castelo Branco | 2021/07/29 08:30 | Garrett Johns v Gilbert S K Junior | 5-7,3-6 |
| ITF M15 Castelo Branco | 2021/07/27 08:30 | Vilius Gaubas v Gilbert S K Junior | 4-6,3-6 |
| 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 Frederiksberg | 2021/08/03 09:20 | Daniel De Jonge v Patrick Kypson | 6-3,7-6 |
| ITF M25 Marburg | 2021/07/05 12:05 | Patrick Zahraj v Daniel De Jonge | 6-3,6-2 |
| ITF M25 The Hague | 2021/07/01 07:30 | Marko Tepavac v Daniel De Jonge | 7-5,6-1 |