Stadium: Court 8 Round: 26 Ground: Clay
| ITF M15 Frederiksberg | 2021/08/03 10:55 | Guy Den Ouden v Sandro Kopp | 4-6,4-6 |
| ITF M15 Vejle | 2021/07/29 08:00 | Zukas, Matias v Sandro Kopp | 6-3,6-1 |
| ITF M15 Vejle | 2021/07/27 08:00 | Elmer Moller v Sandro Kopp | 0-6,5-7 |
| ITF M25 Kottingbrunn | 2021/07/22 08:00 | Giovanni Fonio v Sandro Kopp | 6-1,7-5 |
| ITF M25 Kottingbrunn | 2021/07/21 12:05 | Taiyo Yamanaka v Sandro Kopp | 1-6,2-6 |
| ITF M25 Telfs | 2021/07/16 09:30 | Gonzalo Lama v Sandro Kopp | 6-1,6-2 |
| ITF M25 Telfs | 2021/07/14 08:50 | Vittar, Francisco v Sandro Kopp | 2-6,3-6 |
| ITF - M15 Antalya | 2021/05/18 07:00 | Sandro Kopp v Thomas Deschamps | 6-1,5-7,13-15 |
| ITF M15 Frederiksberg | 2021/08/04 08:00 | Ruzgas, Marius v Kirkov, Vasil | 2-6,2-6 |
| ITF M15 Vejle | 2021/07/30 07:55 | Karl Friberg v Kirkov, Vasil | 6-2,7-6 |
| ITF M15 Vejle | 2021/07/27 12:20 | Adrian Oetzbach v Kirkov, Vasil | 7-5,3-6,3-6 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/18 07:30 | Kirkov, Vasil v Valentin Vanta | 6-3,7-5 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/17 07:00 | Kirkov, Vasil v Adriano Dzhenev | 6-3,6-2 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/16 06:00 | Kirkov, Vasil v Yanaki Milev | 6-1,6-1 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/14 07:30 | Kirkov, Vasil v Aleksandr Braynin | 7-5,5-1 |
| UTR Pro Tennis Series Pazardzhik | 2021/07/13 10:30 | Kirkov, Vasil v Gorazd Srbljak | 2-6,6-3,1-6 |