Stadium: Main Court (7) Round: 44 Ground: Clay
| ITF M25 Kottingbrunn | 2021/07/19 13:45 | Jan Jermar v Francisco Vittar | 4-6,5-7 |
| ITF M25 Kottingbrunn | 2021/07/18 07:30 | Laurin Aerne v Jan Jermar | 1-6,2-6 |
| ITF M25 Telfs | 2021/07/12 07:50 | Neil Oberleitner v Jan Jermar | 6-3,6-0 |
| ITF M15 Poprad | 2021/07/07 10:10 | Luca Castelnuovo v Jan Jermar | 7-6,6-2 |
| ITF M25 Most | 2021/05/24 08:00 | Jakub Beran v Jan Jermar | 6-4,6-7,10-3 |
| ITF M25 Jablonec Nad Nisou | 2021/05/17 07:30 | Jan Jermar v Kai Lemstra | 4-6,4-6 |
| ITF M25 Jablonec Nad Nisou | 2021/05/16 08:30 | Jan Jermar v Peter Samosi | 7-6,6-0 |
| ITF M25 Prague | 2021/05/09 10:00 | Ondrej Horak v Jan Jermar | 7-6,6-3 |