Stadium: Court 5 Round: 26 Ground: Clay
| ITF - M15 Antalya | 2021/05/04 07:00 | Mats Rosenkranz v Gabriele Piraino | 5-7,0-6 |
| ITF - M15 Antalya | 2021/05/03 07:00 | Gabriele Piraino v Vladimir Korolev | 6-3,6-1 |
| ITF - M15 Antalya | 2021/05/05 11:40 | Louroi Martinez v Adrian Andreev | 5-7,6-7 |
| Challenger - Oeiras | 2021/04/08 10:00 | Pedro Cachin v Adrian Andreev | 6-2,6-4 |
| Challenger - Oeiras | 2021/04/06 12:00 | Chun Hsin Tseng v Adrian Andreev | 6-1,6-7,3-6 |
| Challenger - Oeiras - Calificari | 2021/04/04 11:30 | Eduard Esteve Lobato v Adrian Andreev | 3-6,4-6 |
| ITF - M25 Biel | 2021/03/30 13:50 | Adrian Andreev v Tim Van Rijthoven | 3-6,1-6 |
| Challenger - Lille | 2021/03/21 09:00 | Adrian Andreev v Christopher Heyman | 4-6,6-3,3-6 |
| Cupa Davis | 2021/03/05 15:10 | Adrian Andreev v Gerardo L Villasenor | 6-3,1-6,2-6 |
| ATP - Singapore | 2021/02/24 11:10 | Adrian Andreev v Alexei Popyrin | 1-6,7-5,3-6 |