# 2021 Rafa Nadal Open – Singles

Emil Ruusuvuori was the defending champion but chose not to defend his title.
Lukáš Lacko won the title after defeating Yasutaka Uchiyama 5–7, 7–6$^{(10–8)}$, 6–1 in the final.

## Seeds

* Yasutaka Uchiyama (final)
* Fernando Verdasco (quarterfinals)
* Liam Broady (first round)
* João Sousa (quarterfinals)
* Sebastian Ofner (second round, retired)
* Marcelo Tomás Barrios Vera (second round)
* Kacper Żuk (first round)
* Blaž Rola (first 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 | Final |
| 1 | Yasutaka Uchiyama | 4 | 6 | 7 | | | | | |
| Q | Michael Geerts | 6 | 1 | 5 | | | | | |
| Q | Michael Geerts | 6 | 1 | 5 | 1 | Yasutaka Uchiyama | 7 | 6$^8$ | 1 |
| | | | | | | Lukáš Lacko | 5 | 7$^{10}$ | 6 |
| | Lukáš Lacko | 6 | 6 | | | Lukáš Lacko | 5 | 7$^{10}$ | 6 |
| | Tobias Kamke | 0 | 3 | | | | | | |

### 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 | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | Y Uchiyama | 4 | 3 | | | | | | | | | | | | | | | | |
| | S Diez | 6 | 3$^r$ | | 1 | Y Uchiyama | 6 | 6 | | | | | | | | | | | |
| Q | A González | 7$^7$ | 6$^1$ | 4 | LL | J Zieliński | 1 | 2 | | | | | | | | | | | |
| LL | J Zieliński | 6$^5$ | 7$^7$ | 6 | | | | | | 1 | Y Uchiyama | 4 | 6 | 7$^7$ | | | | | |
| | R Ramanathan | 6$^1$ | 6 | 7 | | | | | | | R Ramanathan | 6 | 4 | 6$^5$ | | | | | |
| WC | C Gómez-Herrera | 7$^7$ | 4 | 5 | | R Ramanathan | 7 | 0 | | | | | | | | | | | |
| Alt | R Quiroz | 7$^7$ | 3 | 2 | 5 | S Ofner | 5 | 0$^r$ | | | | | | | | | | | |
| 5 | S Ofner | 6$^5$ | 6 | 6 | | | | | | | | | | | 1 | Y Uchiyama | 4 | 6 | 7 |
| 4 | J Sousa | 6 | 1 | 7 | | | | | | | | | | | Q | M Geerts | 6 | 1 | 5 |
| Alt | H Moriya | 4 | 6 | 5 | 4 | J Sousa | 6 | 6 | | | | | | | | | | | |
| Alt | R Ortega Olmedo | 7 | 7 | | Alt | R Ortega Olmedo | 3 | 3 | | | | | | | | | | | |
| Alt | N Mejía | 5 | 5 | | | | | | | 4 | J Sousa | 6 | 3 | 4 | | | | | |
| Q | M Geerts | 4 | 6 | 6 | | | | | | Q | M Geerts | 2 | 6 | 6 | | | | | |
| | T Ito | 6 | 2 | 1 | Q | M Geerts | 4 | 6 | 6 | | | | | | | | | | |
| WC | N Álvarez Varona | 4 | 6$^3$ | | 6 | MT Barrios Vera | 6 | 2 | 1 | | | | | | | | | | |
| 6 | MT Barrios Vera | 6 | 7$^7$ | | | | | | | | | | | | | | | | |

### 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 | Semifinals | Semifinals | Semifinals |
| 7 | K Żuk | 3 | 4 | | | | | | | | | | | | | |
| | D Kuzmanov | 6 | 6 | | | D Kuzmanov | 2 | 6$^9$ | | | | | | | | |
| Q | J Härteis | 2 | 3 | | | L Lacko | 6 | 7$^{11}$ | | | | | | | | |
| | L Lacko | 6 | 6 | | | | | | | | L Lacko | 7 | 7 | | | |
| | B Tomic | 3 | 1 | | | | | | | | F Ferreira Silva | 5 | 5 | | | |
| | F Ferreira Silva | 6 | 6 | | | F Ferreira Silva | 3 | 7 | 6 | | | | | | | |
| | M Viola | 6 | 3 | 6 | | M Viola | 6 | 5 | 0 | | | | | | | |
| 3 | L Broady | 4 | 6 | 4 | | | | | | | | | | L Lacko | 6 | 6 |
| 8 | B Rola | 4 | 4 | | | | | | | | | | | T Kamke | 0 | 3 |
| | T Kamke | 6 | 6 | | | T Kamke | 6 | 6 | | | | | | | | |
| Q | N Chappell | 6 | 6 | | Q | N Chappell | 2 | 4 | | | | | | | | |
| Alt | E Karlovskiy | 3 | 1 | | | | | | | | T Kamke | 6 | 6 | | | |
| WC | D Rincón | 3 | 6 | 1 | | | | | | 2 | F Verdasco | 3 | 1 | | | |
| Alt | S Kozlov | 6 | 1 | 6 | Alt | S Kozlov | 6 | 6$^6$ | 2 | | | | | | | |
| LL | N Moreno de Alboran | 3 | 2 | | 2 | F Verdasco | 1 | 7$^8$ | 6 | | | | | | | |
| 2 | F Verdasco | 6 | 6 | | | | | | | | | | | | | |