Stadium: Court 1 Round: 25 Ground: Clay
| ITF M25 Denia | 2021/07/25 08:00 | Denis Klok v Lorenzo Joaquin Rodriguez | 6-7,1-6 |
| ITF M25 Gandia | 2021/07/19 09:00 | Denis Klok v Nacho Serra Sanchez | 6-7,6-0,2-10 |
| ITF M25 Gandia | 2021/07/18 07:00 | Denis Klok v Hans Albert Schubert | 6-3,6-2 |
| ITF M15 Sofia | 2021/07/07 07:00 | Denis Klok v Aleksandr Braynin | 4-6,3-6 |
| ITF M25 Belgrade | 2021/06/27 07:00 | Denis Klok v George Botezan | 3-6,1-6 |
| ITF M15 Antalya | 2021/04/28 11:40 | Francesco Maestrelli v Denis Klok | 1-6,6-2,6-1 |
| ITF M15 Antalya | 2021/04/27 07:00 | Denis Klok v Vladimir Korolev | 6-1,4-6,10-3 |
| ITF M15 Antalya | 2021/04/26 07:00 | Denis Klok v Vojtech Mares | 6-3,6-2 |
| ITF M15 Zilina | 2021/09/01 08:00 | Lukas Palovic v Bastian Malla | 2-6,6-7 |
| ITF M15 Zilina | 2021/08/31 07:30 | Lukas Palovic v Dung Em Oliver Dao | 6-2,7-6 |
| ITF M15 Bratislava | 2021/08/25 08:00 | Lukas Palovic v Danylo Kalenichenko | 2-6,2-6 |
| ITF M15 Bratislava | 2021/08/18 08:00 | Robin Stanek v Lukas Palovic | 7-6,6-1 |
| ITF M15 Novi Sad | 2021/08/04 11:20 | Filip Misolic v Lukas Palovic | 6-4,6-4 |
| ITF M15 Novi Sad | 2021/08/03 08:00 | Koray Kirci v Lukas Palovic | 6-3,4-6,7-10 |
| ITF M15 Novi Sad | 2021/08/02 11:00 | Dusan Rajic v Lukas Palovic | 4-6,1-6 |
| ITF M15 Novi Sad | 2021/08/01 14:00 | Stefanos Sakellaridis v Lukas Palovic | 4-6,1-6 |