# 2021 Aberto da República – Men's singles

This was the first edition of the tournament.
Federico Coria won the title after defeating Jaume Munar 7–5, 6–3 in the final.

## Seeds

* Federico Coria (champion)
* Jaume Munar (final)
* Sebastián Báez (withdrew)
* Francisco Cerúndolo (semifinals, retired)
* Hugo Dellien (second round)
* Tomás Martín Etcheverry (first round)
* Thiago Seyboth Wild (quarterfinals)
* Juan Ignacio Londero (quarterfinals)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| 1 | Federico Coria | 6 | 2 | | | | | |
| 4 | Francisco Cerúndolo | 1 | 1$^r$ | | | | | |
| 4 | Francisco Cerúndolo | 1 | 1$^r$ | | 1 | Federico Coria | 7 | 6 |
| | | | | | 2 | Jaume Munar | 5 | 3 |
| | Pedro Cachin | 3 | 7$^7$ | 3 | 2 | Jaume Munar | 5 | 3 |
| 2 | Jaume Munar | 6 | 6$^2$ | 6 | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | F Coria | 6 | 7$^9$ | | | | | | | | | | | | | | |
| Q | L Darderi | 3 | 6$^7$ | | 1 | F Coria | 6 | 7$^7$ | | | | | | | | | |
| WC | Wilson Leite | 6 | 6 | | WC | W Leite | 4 | 6$^5$ | | | | | | | | | |
| | A Collarini | 4 | 4 | | | | | | | 1 | F Coria | 7$^{12}$ | 6 | | | | |
| | F Meligeni Alves | 4 | 6 | 2 | | | | | | 8 | JI Londero | 6$^{10}$ | 4 | | | | |
| | P Sakamoto | 6 | 3 | 0$^r$ | | F Meligeni Alves | 4 | 6$^6$ | | | | | | | | | |
| | J Nikles | 4 | 4 | | 8 | JI Londero | 6 | 7$^8$ | | | | | | | | | |
| 8 | JI Londero | 6 | 6 | | | | | | | | | | | 1 | F Coria | 6 | 2 |
| 4 | F Cerúndolo | 6 | 6 | | | | | | | | | | | 4 | F Cerúndolo | 1 | 1$^r$ |
| LL | J Pereira | 2 | 1 | | 4 | F Cerúndolo | 5 | 6 | 6 | | | | | | | | |
| | GA Olivieri | 2 | 6 | 6 | | GA Olivieri | 7 | 3 | 4 | | | | | | | | |
| | M Pucinelli de Almeida | 6 | 2 | 4 | | | | | | 4 | F Cerúndolo | 7$^7$ | 6 | | | | |
| WC | G Heide | 7 | 1 | 5 | | | | | | | H Casanova | 6$^3$ | 4 | | | | |
| | H Casanova | 5 | 6 | 7 | | H Casanova | 6 | 6 | | | | | | | | | |
| | N Jarry | 3 | 6 | 5 | 5 | H Dellien | 4 | 4 | | | | | | | | | |
| 5 | H Dellien | 6 | 3 | 7 | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 6 | TM Etcheverry | 6 | 6$^4$ | 4 | | | | | | | | | | | | | | | |
| | N Kicker | 4 | 7$^7$ | 6 | | N Kicker | 7$^7$ | 7$^8$ | | | | | | | | | | | |
| | JP Ficovich | 6 | 3 | | | JP Ficovich | 6$^5$ | 6$^6$ | | | | | | | | | | | |
| | O Luz | 4 | 0$^r$ | | | | | | | | N Kicker | 6$^3$ | 4 | | | | | | |
| | P Cachin | 7 | 7 | | | | | | | | P Cachin | 7$^7$ | 6 | | | | | | |
| WC | M Alves | 5 | 5 | | | P Cachin | 3 | 6 | 7$^7$ | | | | | | | | | | |
| | Gilbert Klier Júnior | 6 | 7$^7$ | | | G Klier Júnior | 6 | 3 | 6$^5$ | | | | | | | | | | |
| Q | A Gómez | 3 | 6$^4$ | | | | | | | | | | | | | P Cachin | 3 | 7$^7$ | 3 |
| 7 | T Seyboth Wild | 7$^7$ | 6 | | | | | | | | | | | | 2 | J Munar | 6 | 6$^2$ | 6 |
| | F Díaz Acosta | 6$^1$ | 3 | | 7 | T Seyboth Wild | 7$^7$ | 5 | 4 | | | | | | | | | | |
| Q | B Bobrov | 3 | 6$^3$ | | | N Álvarez Varona | 6$^4$ | 7 | 2$^r$ | | | | | | | | | | |
| | N Álvarez Varona | 6 | 7$^7$ | | | | | | | 7 | T Seyboth Wild | 1 | 6 | 4 | | | | | |
| Q | T Lipovšek Puches | 1 | 0 | | | | | | | 2 | J Munar | 6 | 3 | 6 | | | | | |
| | S Rodríguez Taverna | 6 | 6 | | | S Rodríguez Taverna | 6 | 2 | 1 | | | | | | | | | | |
| Alt | A González | 2 | 6 | 3 | 2 | J Munar | 4 | 6 | 6 | | | | | | | | | | |
| 2 | J Munar | 6 | 3 | 6 | | | | | | | | | | | | | | | |