# 2021 Uruguay Open – Singles

Jaume Munar was the defending champion but lost in the semifinals to Juan Ignacio Londero.
Hugo Dellien won the title after defeating Londero 6–0, 6–1 in the final.

## Seeds

* Federico Coria (semifinals)
* Jaume Munar (semifinals)
* Facundo Bagnis (quarterfinals, retired)
* Thiago Monteiro (quarterfinals)
* Francisco Cerúndolo (first round)
* Juan Pablo Varillas (second round)
* Hugo Dellien (champion)
* Tomás Martín Etcheverry (second round)

## 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 | 6$^5$ | 6$^4$ | | | | |
| 7 | Hugo Dellien | 2 | 7$^7$ | 7$^7$ | | | | |
| 7 | Hugo Dellien | 2 | 7$^7$ | 7$^7$ | 7 | Hugo Dellien | 6 | 6 |
| | | | | | | Juan Ignacio Londero | 0 | 1 |
| | Juan Ignacio Londero | 0 | 6 | 6 | | Juan Ignacio Londero | 0 | 1 |
| 2 | Jaume Munar | 6 | 4 | 4 | | | | |

### 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 | Semifinals |
| 1 | F Coria | 6 | 5 | 6 | | | | | | | | | | | | | | |
| | A Collarini | 3 | 7 | 3 | 1 | F Coria | 6 | 6 | | | | | | | | | | |
| | MT Barrios Vera | 4 | 5 | | | M Pucinelli de Almeida | 0 | 3 | | | | | | | | | | |
| | M Pucinelli de Almeida | 6 | 7 | | | | | | | 1 | F Coria | 6 | 6 | | | | | |
| | TA Tirante | 6 | 3 | 6$^3$ | | | | | | Alt | S Rodríguez Taverna | 3 | 4 | | | | | |
| Alt | S Rodríguez Taverna | 4 | 6 | 7$^7$ | Alt | S Rodríguez Taverna | 3 | 7$^7$ | 7$^8$ | | | | | | | | | |
| WC | F Roncadelli | 3 | 1 | | 6 | JP Varillas | 6 | 6$^4$ | 6$^6$ | | | | | | | | | |
| 6 | JP Varillas | 6 | 6 | | | | | | | | | | | 1 | F Coria | 6 | 6$^5$ | 6$^4$ |
| 3 | F Bagnis | 6 | 7$^7$ | | | | | | | | | | | 7 | H Dellien | 2 | 7$^7$ | 7$^7$ |
| Q | G Villanueva | 1 | 6$^4$ | | 3 | F Bagnis | 6 | 7 | | | | | | | | | | |
| Q | F Comesaña | 6 | 7 | | Q | F Comesaña | 4 | 5 | | | | | | | | | | |
| Q | Facundo Juárez | 4 | 5 | | | | | | | 3 | F Bagnis | 6$^4$ | 1$^r$ | | | | | |
| | A Tabilo | 3 | 4 | | | | | | | 7 | H Dellien | 7$^7$ | 4 | | | | | |
| | T Skatov | 6 | 6 | | | T Skatov | 4 | 6 | 3 | | | | | | | | | |
| WC | F Llanes | 2 | 4 | | 7 | H Dellien | 6 | 4 | 6 | | | | | | | | | |
| 7 | H Dellien | 6 | 6 | | | | | | | | | | | | | | | |

### 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 | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 5 | F Cerúndolo | 4 | 6 | 2 | | | | | | | | | | | | | | |
| | JI Londero | 6 | 4 | 6 | | JI Londero | 6 | 6 | | | | | | | | | | |
| Alt | H Casanova | 6 | 7$^7$ | | Alt | H Casanova | 4 | 2 | | | | | | | | | | |
| | F Meligeni Alves | 3 | 6$^3$ | | | | | | | | JI Londero | 6 | 7$^7$ | | | | | |
| | JP Ficovich | 6 | 6 | | | | | | | 4 | T Monteiro | 3 | 6$^1$ | | | | | |
| WC | M Cuevas | 3 | 2 | | | JP Ficovich | 1 | 2 | | | | | | | | | | |
| | R Olivo | 7$^7$ | 2 | 6$^4$ | 4 | T Monteiro | 6 | 6 | | | | | | | | | | |
| 4 | T Monteiro | 6$^2$ | 6 | 7$^7$ | | | | | | | | | | | JI Londero | 0 | 6 | 6 |
| 8 | TM Etcheverry | 6 | 6 | | | | | | | | | | | 2 | J Munar | 6 | 4 | 4 |
| Alt | GA Olivieri | 1 | 4 | | 8 | TM Etcheverry | 6 | 2 | 5 | | | | | | | | | |
| | C Ugo Carabelli | 3 | 6 | 6 | | C Ugo Carabelli | 4 | 6 | 7 | | | | | | | | | |
| Q | L Darderi | 6 | 3 | 4 | | | | | | | C Ugo Carabelli | 4 | 1 | | | | | |
| | G Andreozzi | 6 | 3 | 3 | | | | | | 2 | J Munar | 6 | 6 | | | | | |
| | P Cachin | 4 | 6 | 6 | | P Cachin | 4 | 6$^4$ | | | | | | | | | | |
| | F Mena | 1 | 2 | | 2 | J Munar | 6 | 7$^7$ | | | | | | | | | | |
| 2 | J Munar | 6 | 6 | | | | | | | | | | | | | | | |