| Singles | |
|---|---|
| 2018 San Luis Open Challenger Tour | |
| Champion |  Marcelo Arévalo |
| Runner-up |  Roberto Cid Subervi |
| Score | 6–3, 6–7(3–7), 6–4 |
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.
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)| Semifinals | Final | ||||||||||||
| Q | Roberto Cid Subervi | 6 | 6 | ||||||||||
| Q | Pedro Sakamoto | 3 | 3 | ||||||||||
| Q | Roberto Cid Subervi | 3 | 77 | 4 | |||||||||
| Marcelo Arévalo | 6 | 63 | 6 | ||||||||||
 Daniel Elahi Galán | 6 | 4 | 3 | ||||||||||
| Marcelo Arévalo | 4 | 6 | 6 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | P Lorenzi | 77 | 1 | 3 | |||||||||||||||||||||||
| A Krajicek | 62 | 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 | 65 | 7 | 6 | ||||||||||||||||||||
| F Bagnis | 6 | 1 | 6 | F Bagnis | 77 | 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 | 64 | ||||||||||||||||||||
| F Coria | 3 | 4 | Q | P Sakamoto | 6 | 77 | |||||||||||||||||||||
| 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 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 6 | E King | 3 | 3 | ||||||||||||||||||||||||
| A González | 6 | 6 | A González | 3 | 4 | ||||||||||||||||||||||
| WC | L Gómez | 3 | 64 | Q | G Escobar | 6 | 6 | ||||||||||||||||||||
| Q | G Escobar | 6 | 77 | Q | G Escobar | 2 | 3 | ||||||||||||||||||||
| DE Galán | 62 | 77 | 7 | DE Galán | 6 | 6 | |||||||||||||||||||||
| J Souza | 77 | 64 | 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 | 77 | ||||||||||||||||||||||
 D Muñoz de la Nava | 6 | 7 | D Muñoz de la Nava | 3 | 64 | ||||||||||||||||||||||
| 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 | 1r | ||||||||||||||||||||||||
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