Stadium: Court 4 Round: 28 Ground: Hardcourt outdoor
| ITF M15 Monastir | 2021/05/08 08:30 | Lucas Catarina v Alexander Donski | 7-6,1-6,6-4 |
| ITF Bulgaria F1 | 2018/05/16 07:00 | Lucas Catarina v Alexander Donski | 6-2,6-2 |
| Challenger Santiago | 2021/10/12 20:15 | Lucas Catarina v Tomas Barrios Vera | 5-7,2-6 |
| Challenger Santiago | 2021/10/11 16:50 | Lucas Catarina v Nicolas Alvarez | 6-1,3-6,4-6 |
| Challenger Santiago Qual | 2021/10/10 15:45 | Lucas Catarina v Nicolas Barrientos | 6-4,7-5 |
| Challenger Santiago | 2021/10/05 15:35 | Hugo Dellien v Lucas Catarina | 4-6,6-3,6-3 |
| Challenger Lima | 2021/09/27 19:10 | Lucas Catarina v Renzo Olivo | 4-6,4-6 |
| Challenger Ambato | 2021/09/23 18:50 | Lucas Catarina v Facundo Mena | 6-4,6-7,4-6 |
| Challenger Ambato | 2021/09/22 15:00 | Mirza Basic v Lucas Catarina | 6-7,4-6 |
| Challenger Quito | 2021/09/14 16:30 | Lucas Catarina v Juan Pablo Ficovich | 2-6,4-6 |
| ITF M15 Sozopol | 2021/10/14 15:10 | Simeon Terziev v Alexander Donski | 6-4,6-4 |
| ITF M15 Sozopol | 2021/10/13 09:00 | Dragomir Draganov v Alexander Donski | 1-6,2-6 |
| ITF M15 Sozopol | 2021/10/09 07:00 | Alexander Donski v Kai Wehnelt | 6-4,3-6,6-7 |
| ITF M15 Sozopol | 2021/10/08 08:35 | Tim Handel v Alexander Donski | 3-6,6-3,2-6 |
| ITF M15 Sozopol | 2021/10/05 15:15 | Dragos Constantin Ignat v Alexander Donski | 1-6,2-6 |
| ATP Sofia | 2021/09/27 09:00 | Andreas Seppi v Alexander Donski | 6-3,6-2 |
| ATP Sofia | 2021/09/26 09:00 | Alexander Donski v Jurij Rodionov | 2-6,6-1,7-6 |
| ITF M25 Plaisir | 2021/09/16 09:55 | Robin Bertrand v Alexander Donski | 3-6,3-6 |