Stadium: Court 3 Round: 54 Ground: Carpet indoor
| ITF M25 Plaisir | 2021/09/13 10:15 | Niklas Schell v Warren Sinius | 2-6,6-4,10-8 |
| ITF M25 Plaisir | 2021/09/12 12:30 | Pierre Antoine Tailleu v Warren Sinius | 6-7,3-6 |
| UTR Pro Tennis Series Sofia | 2021/09/01 06:30 | Valentin Vanta v Warren Sinius | 6-1,5-0 |
| UTR Pro Tennis Series Sofia | 2021/08/31 09:30 | Volodymyr Uzhylovskyi v Warren Sinius | 6-2,5-4 |
| UTR Pro Tennis Series Sofia | 2021/08/30 12:00 | Warren Sinius v George Lazarov | 2-6,2-5 |
| UTR Pro Tennis Series Zadar | 2021/07/04 07:00 | Bozo Barun v Warren Sinius | 6-1,6-0 |
| UTR Pro Tennis Series Zadar | 2021/07/01 09:30 | Warren Sinius v Jerko Brkic | 6-3,6-5 |
| UTR Pro Tennis Series Zadar | 2021/06/30 08:00 | Warren Sinius v Constant De La Bassetiere | 3-6,6-6 |
| UTR Pro Tennis Series Ricany | 2021/09/12 10:30 | Michalis Sakellaridis v Dominik Langmajer | 6-2,5-2 |
| UTR Pro Tennis Series Ricany | 2021/09/11 07:30 | Dominik Langmajer v Alec Adamson | 3-6,6-3,6-3 |
| ITF M25 Ricany | 2021/08/29 12:00 | Dominik Langmajer v Martin Machala | 3-6,3-6 |
| ITF M25 Poznan | 2021/08/22 08:00 | Dominik Langmajer v Marcelo Zormann | 4-6,1-6 |
| ITF M15 Lodz | 2021/08/15 11:00 | Omar Brigida v Dominik Langmajer | 6-1,6-4 |
| ITF M15 Gdynia | 2021/08/08 08:00 | Olaf Pieczkowski v Dominik Langmajer | 6-2,6-1 |
| ITF M25 Grodzisk Mazowiecki | 2021/08/01 09:55 | Dominik Langmajer v Yujiro Onuma | 3-6,3-6 |
| ITF M15 Castelo Branco | 2021/07/26 11:00 | Adan Freire Da Silva v Dominik Langmajer | 6-3,6-2 |