Stadium: Court 2 Round: 44 Ground: Clay
| ITF - M15 Novomoskovsk | 2021/05/24 12:00 | Gabriel Donev v Dzianis Zharyn | 7-6,6-7,10-6 |
| ITF - M15 Káhira | 2021/05/07 10:15 | Gabriel Donev v Oliver Crawford | 6-3,2-6,2-6 |
| ITF - M15 Káhira | 2021/05/06 08:00 | Gabriel Donev v Volodymyr Uzhylovskyi | 6-1,6-1 |
| ITF - M15 Káhira | 2021/05/04 09:45 | Gabriel Donev v Benedikt Emesz | 6-2,6-2 |
| ITF - M15 Káhira | 2021/05/03 08:00 | Gabriel Donev v Santiago De La Fuente | 7-5,1-6,17-15 |
| ITF - M15 Káhira | 2021/04/28 09:35 | Carlos Sanchez Jover v Gabriel Donev | 6-1,6-2 |
| UTR Pro Tennis Series - Pazardžik | 2021/04/10 10:30 | Gergely Madarasz v Gabriel Donev | 4-6,6-3,6-0 |
| UTR Pro Tennis Series - Pazardžik | 2021/04/09 11:30 | Gabriel Donev v Ronan Joncour | 5-7,3-6 |
| ITF - M15 Novomoskovsk | 2021/05/24 12:00 | Olexiy Kolisnyk v Alexander Zgirovsky | 7-6,2-6,8-10 |
| ITF - M15 Novomoskovsk | 2021/05/23 08:00 | Egor Matvievici v Alexander Zgirovsky | 1-6,3-6 |
| ITF - M15 Petrohrad | 2021/04/12 08:30 | Daniil Glinka v Alexander Zgirovsky | 7-6,7-6 |
| ITF - M15 Petrohrad - kvalifikácia | 2021/04/11 11:00 | Leonid Sheyngezikht v Alexander Zgirovsky | 6-4,4-6,4-10 |
| ITF - M15 Petrohrad | 2021/04/04 13:40 | Igor Trunov v Alexander Zgirovsky | 1-6,6-3,10-7 |
| ITF - M15 Kazaň | 2021/03/09 06:55 | Alexander Zgirovsky v Pavel Verbin | 6-4,6-7,6-10 |
| ITF - M15 Kazaň | 2021/03/08 11:15 | Alexander Zgirovsky v Dmitry Dolzhenkov | 7-6,6-3 |
| ITF - M15 Monastir | 2021/01/10 12:30 | Paras Dahiya v Alexander Zgirovsky | 6-4,6-0 |