Stadium: Court 2 Round: 25
| ITF M25 Portoviejo | 2021/07/29 14:25 | March, Antonio Cayetano v Hernandez Serrano, Juan Alejandro | 6-3,7-6 |
| ATP - Los Cabos | 2021/07/18 00:00 | Hernandez Serrano, Juan Alejandro v Nicolas Mejia | 3-6,6-3,5-7 |
| ITF - M25 Santo Domingo | 2021/06/12 13:30 | Ribeiro Marcondes, Igor v Hernandez Serrano, Juan Alejandro | 7-5,2-6,7-5 |
| ITF - M25 Santo Domingo | 2021/06/11 13:30 | Conner Huertas Del Pino v Hernandez Serrano, Juan Alejandro | 3-6,5-7 |
| ITF - M25 Santo Domingo | 2021/06/08 19:45 | Hernandez Serrano, Juan Alejandro v Rowland Phillips | 6-1,3-6,10-8 |
| ITF - M25 Santo Domingo | 2021/06/01 13:00 | Hernandez Serrano, Juan Alejandro v Hernandez Ramirez, Sergio Luis | 6-4,6-3 |
| ITF - M25 Pensacola | 2021/05/20 14:25 | Hernandez Serrano, Juan Alejandro v Gonzalez, Alejandro | 3-6,2-6 |
| ITF - M25 Pensacola | 2021/05/18 16:05 | Hernandez Serrano, Juan Alejandro v Abraham Asaba | 6-1,6-2 |
| ITF M25 Portoviejo | 2021/07/31 15:00 | Nicolas Alvarez v Huertas Del Pino Cordova, Arklon | 1-6,4-6 |
| ITF M25 Portoviejo | 2021/07/30 14:30 | Nicolas Alvarez v Jose Pereira | 7-6,6-3 |
| ITF M25 Portoviejo | 2021/07/29 16:35 | Nicolas Alvarez v Noah Schachter | 6-2,6-2 |
| Tulsa, Singles Main, M-ITF-USA-16A | 2021/06/17 01:55 | Ezekiel Clark v Nicolas Alvarez | 6-4,6-2 |
| Orlando, USA | 2021/06/07 14:00 | Nicolas Mejia v Nicolas Alvarez | 6-3,7-5 |
| Orlando, USA | 2021/06/06 16:20 | Strong Kirchheimer v Nicolas Alvarez | 3-6,5-7 |
| Challenger - Oeiras | 2021/05/23 11:35 | Nicolas Alvarez v Timofey Skatov | 3-6,2-6 |
| ITF - M25 Vic | 2021/05/18 09:50 | Nicolas Alvarez v Hamou, Maxime | 6-4,0-6,6-7 |