Stadium: Court 23 Round: 25 Ground: Clay
| ITF M15 Antalya | 2021/05/09 08:50 | Alexander Erler v Adrian Andreev | 6-4,6-1 |
| ITF M15 Antalya | 2021/05/08 07:30 | Sandro Ehrat v Adrian Andreev | 1-6,7-5,3-6 |
| ITF M15 Antalya | 2021/05/07 08:35 | Sandro Kopp v Adrian Andreev | 3-6,4-6 |
| ITF M15 Antalya | 2021/05/06 11:40 | Gabriele Piraino v Adrian Andreev | 3-6,2-6 |
| 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 Qual | 2021/04/04 11:30 | Eduard Esteve Lobato v Adrian Andreev | 3-6,4-6 |
| ITF M25 Pensacola | 2021/05/18 14:30 | Nicolas Barrientos v Alexander Bernard | 4-6,6-1,10-4 |
| ITF M25 Pensacola | 2021/05/17 15:30 | Nicolas Barrientos v Tennyson Whiting | 6-2,6-3 |
| UTR Pro Tennis Series California | 2021/02/27 21:30 | Ryan James Storrie v Nicolas Barrientos | 2-6,6-1,3-0 |
| UTR Pro Tennis Series California | 2021/02/26 20:00 | Joshua Sheehy v Nicolas Barrientos | 5-7,4-5 |
| UTR Pro Tennis Series California | 2021/02/25 20:00 | Mousheg Hovhannisyan v Nicolas Barrientos | 5-7,3-6 |
| UTR Pro Tennis Series California | 2021/02/24 16:00 | Blu Baker v Nicolas Barrientos | 0-6,4-6 |
| UTR Pro Tennis Series California | 2021/02/22 20:00 | Spencer Johnson v Nicolas Barrientos | 3-6,2-6 |
| UTR Pro Tennis Series California | 2021/02/20 19:00 | Isaiah Strode v Nicolas Barrientos | 6-4,6-3 |