Stadium: Court 5 Round: 26 Ground: Clay
| ITF M15 Vejle | 2021/07/28 07:55 | Tommaso Compagnucci v Karl Friberg | 4-6,7-5,4-6 |
| ITF M15 Helsinki | 2021/06/05 07:00 | Karl Friberg v Kyrian Jacquet | 5-7,1-6 |
| ITF M15 Helsinki | 2021/06/04 10:50 | Jaimee Floyd Angele v Karl Friberg | 5-7,6-4,3-6 |
| ITF M15 Helsinki | 2021/06/03 09:30 | Sean Cuenin v Karl Friberg | 4-6,4-6 |
| ITF M15 Helsinki | 2021/06/02 08:15 | Karl Friberg v Cristian Rodriguez | 7-6,2-6,6-4 |
| ITF M15 Antalya | 2021/05/19 09:55 | Karl Friberg v Nick Hardt | 1-6,1-6 |
| ITF M15 Antalya | 2021/05/10 07:00 | Karl Friberg v Valentin Vanta | 3-6,6-7 |
| ITF M15 Antalya | 2021/05/09 07:00 | Karl Friberg v Stefanos Sakellaridis | 6-3,6-4 |
| ITF M15 Vejle | 2021/07/27 12:20 | Adrian Oetzbach v Vasil Kirkov | 7-5,3-6,3-6 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/18 07:30 | Vasil Kirkov v Valentin Vanta | 6-3,7-5 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/17 07:00 | Vasil Kirkov v Adriano Dzhenev | 6-3,6-2 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/16 06:00 | Vasil Kirkov v Yanaki Milev | 6-1,6-1 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/14 07:30 | Vasil Kirkov v Aleksandr Braynin | 7-5,5-1 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/13 10:30 | Vasil Kirkov v Gorazd Srbljak | 2-6,6-3,1-6 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/12 06:00 | Vladimir Popov v Vasil Kirkov | 2-6,4-6 |
| ITF M15 Sofia | 2021/07/06 11:05 | Francisco Comesana v Vasil Kirkov | 6-3,6-2 |