| UTR Pro Tennis Series Zadar | 2021/11/19 09:00 | Deni Zmak v Christos Keisidis | 6-1,6-0 |
| UTR Pro Tennis Series Zadar | 2021/11/18 10:30 | Christos Keisidis v Alexander Chepik | 6-3,6-2 |
| UTR Pro Tennis Series Zadar | 2021/11/16 09:00 | Christos Keisidis v Denis Parshutin | 6-3,6-7,6-3 |
| UTR Pro Tennis Series Zadar | 2021/11/15 12:00 | Olexiy Kolisnyk v Christos Keisidis | 7-5,3-6,4-6 |
| UTR Pro Tennis Series Nis | 2021/10/10 08:00 | Christos Keisidis v Vladimir Popov | 6-1,5-2 |
| UTR Pro Tennis Series Nis | 2021/10/09 11:00 | Christos Keisidis v Lawrence Bataljin | 6-4,6-2 |
| UTR Pro Tennis Series Nis | 2021/10/08 15:45 | Dusan Trunic v Christos Keisidis | 2-6,2-5 |
| UTR Pro Tennis Series Nis | 2021/10/07 08:30 | George Botezan v Christos Keisidis | 6-3,6-3 |
| ITF M15 Cancun | 2022/01/18 15:30 | Ezekiel Clark v Zakhar Trapeznikov | 6-1,6-1 |
| ITF M25 Madrid | 2021/10/25 10:30 | Zakhar Trapeznikov v Vitali Shvets | 6-7,7-5,8-10 |
| ITF M15 Girona | 2021/10/20 08:00 | Zakhar Trapeznikov v Lucas Bouquet | 2-6,6-4,5-7 |
| ITF M15 Girona | 2021/10/19 08:00 | Matvey Minin v Zakhar Trapeznikov | 7-6,5-7,5-10 |
| ITF M15 Platja D'Aro | 2021/10/12 08:30 | Max Houkes v Zakhar Trapeznikov | 6-3,6-4 |
| ITF M15 Platja D'Aro | 2021/10/11 08:30 | Noah Regas v Zakhar Trapeznikov | 3-6,6-1,5-10 |
| ITF M15 Platja D'Aro | 2021/10/10 11:00 | Vicente O Moratalla v Zakhar Trapeznikov | 1-6,2-6 |
| ITF M15 Platja D'Aro | 2021/10/03 11:00 | Kirill Mishkin v Zakhar Trapeznikov | 2-6,6-3,10-1 |