# 2018 San Luis Open Challenger Tour – Singles

Andrej Martin was the defending champion but chose not to defend his title.
Marcelo Arévalo won the title after defeating Roberto Cid Subervi 6–3, 6–7$^{(3–7)}$, 6–4 in the final.

## Seeds

* Paolo Lorenzi (first round)
* Gerald Melzer (first round, retired)
* Yannick Hanfmann (second round)
* Thomaz Bellucci (second round)
* Víctor Estrella Burgos (first round)
* Evan King (first round)
* Mitchell Krueger (first round)
* Peđa Krstin (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 | Final |
| Q | Roberto Cid Subervi | 6 | 6 | | | | | | |
| Q | Pedro Sakamoto | 3 | 3 | | | | | | |
| Q | Pedro Sakamoto | 3 | 3 | | Q | Roberto Cid Subervi | 3 | 7$^7$ | 4 |
| | | | | | | Marcelo Arévalo | 6 | 6$^3$ | 6 |
| | Daniel Elahi Galán | 6 | 4 | 3 | | Marcelo Arévalo | 6 | 6$^3$ | 6 |
| | Marcelo Arévalo | 4 | 6 | 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 | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | P Lorenzi | 7$^7$ | 1 | 3 | | | | | | | | | | | | | | |
| | A Krajicek | 6$^2$ | 6 | 6 | | A Krajicek | 0 | 2 | | | | | | | | | | |
| | F Argüello | 3 | 3 | | | J Hernández-Fernández | 6 | 6 | | | | | | | | | | |
| | J Hernández-Fernández | 6 | 6 | | | | | | | | J Hernández-Fernández | 6 | 3 | 4 | | | | |
| Q | R Cid Subervi | 6 | 6 | | | | | | | Q | R Cid Subervi | 2 | 6 | 6 | | | | |
| | A Sarkissian | 2 | 0 | | Q | R Cid Subervi | 6$^5$ | 7 | 6 | | | | | | | | | |
| | F Bagnis | 6 | 1 | 6 | | F Bagnis | 7$^7$ | 5 | 1 | | | | | | | | | |
| 7 | M Krueger | 1 | 6 | 3 | | | | | | | | | | | Q | R Cid Subervi | 6 | 6 |
| 3 | Y Hanfmann | 1 | 7 | 6 | | | | | | | | | | | Q | P Sakamoto | 3 | 3 |
| | R Quiroz | 6 | 5 | 3 | 3 | Y Hanfmann | 5 | 6 | 4 | | | | | | | | | |
| | J Clarke | 6 | 2 | 6 | | J Clarke | 7 | 2 | 6 | | | | | | | | | |
| WC | T Hank | 2 | 6 | 2 | | | | | | | J Clarke | 3 | 6$^4$ | | | | | |
| | F Coria | 3 | 4 | | | | | | | Q | P Sakamoto | 6 | 7$^7$ | | | | | |
| Q | P Sakamoto | 6 | 6 | | Q | P Sakamoto | 4 | 6 | 7 | | | | | | | | | |
| WC | G López Villaseñor | 2 | 3 | | 8 | P Krstin | 6 | 3 | 5 | | | | | | | | | |
| 8 | P Krstin | 6 | 6 | | | | | | | | | | | | | | | |

### 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 | E King | 3 | 3 | | | | | | | | | | | | | | |
| | A González | 6 | 6 | | | A González | 3 | 4 | | | | | | | | | |
| WC | L Gómez | 3 | 6$^4$ | | Q | G Escobar | 6 | 6 | | | | | | | | | |
| Q | G Escobar | 6 | 7$^7$ | | | | | | Q | G Escobar | 2 | 3 | | | | | |
| | DE Galán | 6$^2$ | 7$^7$ | 7 | | | | | | DE Galán | 6 | 6 | | | | | |
| | J Souza | 7$^7$ | 6$^4$ | 5 | | DE Galán | 6 | 6 | | | | | | | | | |
| | A Collarini | 3 | 4 | | 4 | T Bellucci | 3 | 3 | | | | | | | | | |
| 4 | T Bellucci | 6 | 6 | | | | | | | | | | | DE Galán | 6 | 4 | 3 |
| 5 | V Estrella Burgos | 1 | 4 | | | | | | | | | | | M Arévalo | 4 | 6 | 6 |
| | M Arévalo | 6 | 6 | | | M Arévalo | 6 | 7$^7$ | | | | | | | | | |
| | D Muñoz de la Nava | 6 | 7 | | | D Muñoz de la Nava | 3 | 6$^4$ | | | | | | | | | |
| Q | K Krawietz | 4 | 5 | | | | | | | M Arévalo | 6 | 3 | 6 | | | | |
| WC | M Sánchez | 6 | 6 | | | | | | | J Choinski | 2 | 6 | 3 | | | | |
| | I Nedelko | 0 | 2 | | WC | M Sánchez | 4 | 5 | | | | | | | | | |
| | J Choinski | 6 | 3 | | | J Choinski | 6 | 7 | | | | | | | | | |
| 2 | G Melzer | 1 | 1$^r$ | | | | | | | | | | | | | | |