# 2021 Andalucía Challenger – Singles

Pedro Martínez was the defending champion but chose not to defend his title.
Gianluca Mager won the title after defeating Jaume Munar 2–6, 6–3, 6–2 in the final.

## Seeds

* Roberto Carballés Baena (first round)
* Norbert Gombos (first round)
* Jaume Munar (final)
* Gianluca Mager (champion)
* Pedro Sousa (second round)
* Taro Daniel (quarterfinals)
* Damir Džumhur (second round)
* Evgeny Donskoy (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 |
| | Alessandro Giannessi | 7$^7$ | 4 | 1 | | | | | |
| 4 | Gianluca Mager | 6$^4$ | 6 | 6 | | | | | |
| 4 | Gianluca Mager | 6$^4$ | 6 | 6 | 4 | Gianluca Mager | 2 | 6 | 6 |
| | | | | | 3 | Jaume Munar | 6 | 3 | 2 |
| 3 | Jaume Munar | 7$^7$ | 7 | | 3 | Jaume Munar | 6 | 3 | 2 |
| Alt | Mario Vilella Martínez | 6$^4$ | 5 | | | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | R Carballés Baena | 6 | 3 | 3 | | | | | | | | | | | | | | |
| | H Laaksonen | 1 | 6 | 6 | | H Laaksonen | 3 | 3 | | | | | | | | | | |
| | M Cressy | 1 | 6$^3$ | | | M Kližan | 6 | 6 | | | | | | | | | | |
| | M Kližan | 6 | 7$^7$ | | | | | | | M Kližan | 0 | 3 | | | | | | |
| | J Domingues | 3 | 4 | | | | | | | A Giannessi | 6 | 6 | | | | | | |
| | A Giannessi | 6 | 6 | | | A Giannessi | 6 | 6 | | | | | | | | | | |
| PR | A Kuznetsov | 7$^7$ | 2 | 1 | 5 | P Sousa | 4 | 3 | | | | | | | | | | |
| 5 | P Sousa | 6$^2$ | 6 | 6 | | | | | | | | | | | A Giannessi | 7$^7$ | 4 | 1 |
| 4 | G Mager | 6 | 6 | | | | | | | | | | | 4 | G Mager | 6$^4$ | 6 | 6 |
| Q | C Sánchez Jover | 3 | 2 | | 4 | G Mager | 6 | 6 | | | | | | | | | | |
| Alt | E Ymer | 6 | 6 | | Alt | E Ymer | 4 | 3 | | | | | | | | | | |
| Q | J Barranco Cosano | 1 | 2 | | | | | | 4 | G Mager | 4 | 6 | 6 | | | | | |
| | M Polmans | 3 | 1 | | | | | | | R Marcora | 6 | 3 | 2 | | | | | |
| | R Marcora | 6 | 6 | | | R Marcora | 6 | 7 | | | | | | | | | | |
| | E Gulbis | 6 | 6 | | | E Gulbis | 4 | 5 | | | | | | | | | | |
| 8 | E Donskoy | 2 | 2 | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 6 | T Daniel | 6 | 6 | | | | | | | | | | | | | | |
| WC | L Borg | 1 | 2 | | 6 | T Daniel | 7 | 6 | | | | | | | | | |
| WC | C Gómez-Herrera | 7$^{12}$ | 7$^7$ | | WC | C Gómez-Herrera | 5 | 4 | | | | | | | | | |
| WC | C Gimeno Valero | 6$^{10}$ | 6$^5$ | | | | | | 6 | T Daniel | 6 | 2 | 3 | | | | |
| Q | V Kopřiva | 6 | 3 | 7 | | | | | 3 | J Munar | 4 | 6 | 6 | | | | |
| | L Rosol | 3 | 6 | 5 | Q | V Kopřiva | 4 | 2 | | | | | | | | | |
| | S Ofner | 6$^3$ | 4 | | 3 | J Munar | 6 | 6 | | | | | | | | | |
| 3 | J Munar | 7$^7$ | 6 | | | | | | | | | | | 3 | J Munar | 7$^7$ | 7 |
| 7 | D Džumhur | 6 | 6 | | | | | | | | | | | Alt | M Vilella Martínez | 6$^4$ | 5 |
| Q | N Sánchez Izquierdo | 4 | 4 | | 7 | D Džumhur | 3 | 4 | | | | | | | | | |
| Alt | M Vilella Martínez | 7$^7$ | 6 | | Alt | M Vilella Martínez | 6 | 6 | | | | | | | | | |
| | L Giustino | 6$^4$ | 0 | | | | | | Alt | M Vilella Martínez | 6 | 6 | | | | | |
| | D Petrović | 6 | 3 | 4 | | | | | | N Milojević | 3 | 4 | | | | | |
| | N Milojević | 3 | 6 | 6 | | N Milojević | 6 | 7 | | | | | | | | | |
| Alt | M Janvier | 6 | 6$^4$ | 6 | Alt | M Janvier | 1 | 5 | | | | | | | | | |
| 2 | N Gombos | 4 | 7$^7$ | 3 | | | | | | | | | | | | | |