Stadium: Court C Round: 26 Ground: Clay
| ITF M25 Pardubice | 2021/09/22 11:05 | Daniel Siniakov v Stefanos Sakellaridis | 6-3,6-2 |
| ITF M25 Ricany | 2021/09/01 09:05 | Marek Gengel v Daniel Siniakov | 7-5,6-3 |
| Challenger Prague | 2021/08/24 13:45 | Daniel Siniakov v Igor Sijsling | 4-6,3-6 |
| ITF M25 Prostejov | 2021/08/17 09:15 | Martin Krumich v Daniel Siniakov | 3-6,6-4,7-5 |
| Challenger Liberec | 2021/08/03 15:10 | Nikola Milojevic v Daniel Siniakov | 7-5,6-0 |
| Challenger Liberec | 2021/08/02 10:35 | Daniel Siniakov v David Vega Hernandez | 6-3,7-5 |
| Challenger Liberec | 2021/08/01 16:30 | Geoffrey Blancaneaux v Daniel Siniakov | 2-6,3-6 |
| ITF M15 Poprad | 2021/07/06 07:55 | Illya Beloborodko v Daniel Siniakov | 3-6,7-6,7-5 |
| ITF M25 Pardubice | 2021/09/22 10:15 | Lukas Pokorny v Eric Vanshelboim | 7-6,2-6,1-6 |
| ITF M15 Ulcinj | 2021/09/04 09:00 | Eric Vanshelboim v Gergely Madarasz | 6-4,4-6,4-6 |
| ITF M15 Ulcinj | 2021/09/03 09:00 | Eric Vanshelboim v Rrezart Cungu | 7-5,4-6,6-2 |
| ITF M15 Ulcinj | 2021/09/02 10:30 | Eric Vanshelboim v Dominik Palan | 7-6,6-2 |
| ITF M15 Bad Waltersdorf | 2021/08/26 06:55 | Neil Oberleitner v Eric Vanshelboim | 7-6,6-0 |
| ITF M15 Bad Waltersdorf | 2021/08/25 07:00 | Marco Miceli v Eric Vanshelboim | 3-6,2-6 |
| ITF M25 Guayaquil | 2021/08/04 14:30 | Eric Vanshelboim v Ricardo Rodriguez-Pace | 6-2,3-6,4-6 |
| ITF M25 Portoviejo | 2021/07/29 16:40 | Jose Pereira v Eric Vanshelboim | 4-6,6-2,7-5 |