| UTR Pro Tennis Series California | 2021/05/26 18:24 | Humberto Lopez v Nathan Oppenheim | 6-1,7-5 |
| UTR Pro Tennis Series California | 2021/05/23 16:30 | Nathan Oppenheim v Hiroki Sakagawa | 1-6,1-6 |
| UTR Pro Tennis Series Cancun | 2021/04/10 17:30 | Clemens Graute v Nathan Oppenheim | 6-4,5-7,6-3 |
| UTR Pro Tennis Series Cancun | 2021/04/08 14:30 | Nathan Oppenheim v Jose Antonio Rodriguez Rodriguez | 6-3,6-2 |
| UTR Pro Tennis Series Cancun | 2021/04/07 19:00 | Nathan Oppenheim v Juan A H Serrano | 0-6,0-6 |
| UTR Pro Tennis Series Cancun | 2021/04/06 17:00 | Nathan Oppenheim v Manuel S Montemayor | 2-6,2-6 |
| UTR Pro Tennis Series Cancun | 2021/04/05 16:00 | Nathan Oppenheim v Jean-Baptiste Badon | 4-6,4-6 |
| ITF M25 Santo Domingo | 2021/06/01 15:55 | Gerardo L Villasenor v Diego Hidalgo | 6-4,3-6,3-6 |
| ITF M25 Pensacola | 2021/05/19 14:30 | Aidan Mchugh v Gerardo L Villasenor | 6-4,6-3 |
| ATP Acapulco | 2021/03/16 00:00 | Gerardo L Villasenor v Dominik Koepfer | 4-6,2-6 |
| Davis Cup | 2021/03/06 16:00 | Dimitar Kuzmanov v Gerardo L Villasenor | 6-7,6-4,6-7 |
| Davis Cup | 2021/03/05 15:10 | Adrian Andreev v Gerardo L Villasenor | 6-3,1-6,2-6 |
| ITF M25 Vale Do Lobo | 2021/02/24 12:10 | Gerardo L Villasenor v Pedro Araujo | 4-6,1-6 |
| ITF M15 Antalya | 2021/02/16 07:00 | Oleksii Krutykh v Gerardo L Villasenor | 6-1,7-5 |
| ITF M15 Antalya | 2021/02/08 07:00 | Gerardo L Villasenor v Sebastian Gima | 6-3,1-6,7-10 |