Stadium: Court 3 Round: 54 Ground: Clay
| Challenger Bratislava | 2021/06/06 14:00 | Duje Ajdukovic v Lukas Pokorny | 6-1,7-6 |
| ITF M25 Most | 2021/05/23 08:00 | Niklas Rohrer v Lukas Pokorny | 7-6,6-3 |
| ITF M15 Antalya | 2021/05/09 07:00 | Gabriele Piraino v Lukas Pokorny | 4-6,6-2,10-7 |
| ITF M15 Sharm El Sheikh | 2021/04/07 08:30 | David Poljak v Lukas Pokorny | 6-3,6-3 |
| ITF M15 Sharm El Sheikh | 2021/04/06 07:30 | Karlo Cubelic v Lukas Pokorny | 6-7,1-6 |
| ITF M15 Sharm El Sheikh | 2021/04/05 07:30 | Lukas Pokorny v Shohei Chikami | 7-6,6-4 |
| ITF M15 Sharm El Sheikh | 2021/04/04 07:30 | Lukas Pokorny v Vasilios Caripi | 6-1,6-2 |
| ITF M15 Bratislava | 2021/03/09 13:00 | Jurgen Briand v Lukas Pokorny | 7-5,6-2 |
| ITF M25 Most | 2021/05/24 08:00 | Adan Freire Da Silva v Daniel Siniakov | 6-3,7-6 |
| ITF M25 Most | 2021/05/23 14:00 | Krystof Zapsky v Daniel Siniakov | 4-6,3-6 |
| ITF M25 Jablonec Nad Nisou | 2021/05/19 08:00 | Vitaliy Sachko v Daniel Siniakov | 4-6,6-3,6-4 |
| ITF M25 Prague | 2021/05/09 08:30 | Daniel Siniakov v Jakub Beran | 5-7,4-6 |
| ITF M15 Antalya | 2021/04/25 07:00 | Daniel Siniakov v Dan Alexandru Tomescu | 1-6,1-6 |
| ITF M15 Antalya | 2021/04/21 08:45 | Paul Woerner v Daniel Siniakov | 6-4,6-3 |
| ITF M15 Antalya | 2021/04/20 07:00 | Michel Vernier v Daniel Siniakov | 0-6,7-6,4-10 |
| ITF M15 Antalya | 2021/04/19 07:00 | Daniel Siniakov v Cheong-Eui Kim | 6-4,3-6,11-9 |