Stadium: Court 6 Round: 54 Ground: Clay
| ITF M25 Prostějov | 2021/08/16 08:00 | Dominique Graf v Jakub Kroslak | 6-2,6-4 |
| ITF M25 Prostějov | 2021/08/15 08:00 | Lars Aregger v Jakub Kroslak | 2-6,2-6 |
| ITF M25 Kottingbrunn | 2021/07/19 10:35 | Jakub Kroslak v Peter Makk | 4-6,6-3,6-10 |
| ITF M25 Kottingbrunn | 2021/07/18 07:30 | Roman Postolka v Jakub Kroslak | 4-6,3-6 |
| ITF M15 Poprad | 2021/07/04 11:00 | Jakub Kroslak v Mateusz Terczynski | 6-2,6-7,9-11 |
| ITF M15 Monastir | 2021/03/28 09:00 | Aleksandr Kalinin v Jakub Kroslak | 7-5,7-6 |
| ITF M15 Monastir | 2021/03/22 10:00 | Jakub Kroslak v Aristotelis Thanos | 4-6,2-6 |
| ITF M15 Monastir | 2021/03/21 16:00 | Jakub Kroslak v Tushar Sharma | 6-1,6-1 |
| ITF M15 Bratislava | 2021/08/16 08:00 | Iiro Vasa v Eero Vasa | 1-6,3-6 |
| ITF M15 Parnu | 2021/08/04 10:10 | Iiro Vasa v Otto Virtanen | 5-7,2-6 |
| ITF M15 Parnu | 2021/08/03 08:30 | Martins Rocens v Iiro Vasa | 3-6,7-6,7-10 |
| ITF M15 Vejle | 2021/07/26 08:00 | Adrian Oetzbach v Iiro Vasa | 6-3,7-5 |
| Challenger Tampere | 2021/07/18 12:55 | Iiro Vasa v Arthur Cazaux | 2-6,6-7 |
| ITF M15 Helsinki | 2021/06/02 06:30 | Iiro Vasa v Matvey Minin | 2-6,4-6 |
| ITF M15 Kouvola | 2021/05/26 11:40 | Iiro Vasa v Karl Kiur Saar | 4-6,0-6 |
| ITF M15 Monastir | 2021/04/26 09:00 | Andrea Picchione v Iiro Vasa | 6-2,6-4 |