# 2019 Monterrey Challenger – Singles

David Ferrer was the defending champion but chose not to defend his title.
Alexander Bublik won the title after defeating Emilio Gómez 6–3, 6–2 in the final.

## Seeds

All seeds receive a bye into the second round.
* Tennys Sandgren (semifinals)
* Bradley Klahn (quarterfinals)
* Feliciano López (quarterfinals)
* Casper Ruud (second round)
* Paolo Lorenzi (second round)
* Marcel Granollers (third round)
* Alexander Bublik (champion)
* Peter Polansky (quarterfinals)
* Christopher Eubanks (third round)
* Mitchell Krueger (third round)
* Roberto Quiroz (second round)
* Marcos Giron (quarterfinals)
* James Ward (second round)
* Dominik Köpfer (third round)
* Sebastian Ofner (third round)
* Darian King (third 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

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| 1 | Tennys Sandgren | 6 | 6$^4$ | 6 | | | | | | | | | |
| 12 | Marcos Giron | 1 | 7$^7$ | 0 | | | | | | | | | |
| 12 | Marcos Giron | 1 | 7$^7$ | 0 | 1 | Tennys Sandgren | 6 | 2 | 6$^5$ | | | | |
| | | | | | 7 | Alexander Bublik | 2 | 6 | 7$^7$ | | | | |
| 3 | Feliciano López | 6$^5$ | 3 | | 7 | Alexander Bublik | 2 | 6 | 7$^7$ | | | | |
| 7 | Alexander Bublik | 7$^7$ | 6 | | | | | | | | | | |
| 7 | Alexander Bublik | 7$^7$ | 6 | | | | | | | 7 | Alexander Bublik | 6 | 6 |
| | | | | | | | | | | | Emilio Gómez | 3 | 2 |
| 8 | Peter Polansky | 3 | 6$^5$ | | | | | | | | | | | Emilio Gómez | 3 | 2 |
| | Emilio Gómez | 6 | 7$^7$ | | | | | | | | | | |
| | Emilio Gómez | 6 | 7$^7$ | | | Emilio Gómez | 2 | 6 | 6 | | | | |
| | | | | | | Donald Young | 6 | 3 | 4 | | | | |
| | Donald Young | 7 | 6 | | | Donald Young | 6 | 3 | 4 | | | | |
| 2 | Bradley Klahn | 5 | 4 | | | | | | | | | | |

### Top half
#### Section 1

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 1 | T Sandgren | 4 | 7$^9$ | 6 | | | | | | | | | | |
| | R Olivo | 6 | 7 | | | R Olivo | 6 | 6$^7$ | 2 | | | | | | | | | | |
| | K Uchida | 4 | 5 | | | | | | | 1 | T Sandgren | 7$^7$ | 4 | 6 | | | | | |
| WC | N Mejía | 4 | 6 | 3 | | | | | | 16 | D King | 6$^5$ | 6 | 2 | | | | | |
| | E King | 6 | 3 | 6 | | E King | 6 | 6$^3$ | 1 | | | | | | | | | | |
| | | | | | 16 | D King | 4 | 7$^7$ | 6 | | | | | | | | | | |
| | | | | | | | | | | | | | | | 1 | T Sandgren | 6 | 6$^4$ | 6 |
| | | | | | | | | | | | | | | | 12 | M Giron | 1 | 7$^7$ | 0 |
| | | | | | 12 | M Giron | 6 | 6 | | | | | | | | | | | |
| WC | E Nava | 6 | 3 | 6 | WC | E Nava | 4 | 2 | | | | | | | | | | | |
| | B Gojo | 4 | 6 | 4 | | | | | | 12 | M Giron | 4 | 6 | 6 | | | | | |
| PR | M Przysiężny | 4 | 4 | | | | | | | 6 | M Granollers | 6 | 3 | 4 | | | | | |
| | DE Galán | 6 | 6 | | | DE Galán | 3 | 4 | | | | | | | | | | | |
| | | | | | 6 | M Granollers | 6 | 6 | | | | | | | | | | | |

#### Section 2

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 3 | F López | 7$^7$ | 6 | | | | | | | | | |
| | C Gómez-Herrera | 6 | 6 | | | C Gómez-Herrera | 6$^3$ | 4 | | | | | | | | | |
| | C Altamirano | 1 | 4 | | | | | | | 3 | F López | 7$^7$ | 6 | | | | |
| | JC Aragone | 6 | 3 | 4 | | | | | | 14 | D Köpfer | 6$^4$ | 2 | | | | |
| | MT Barrios Vera | 3 | 6 | 6 | | MT Barrios Vera | 6$^2$ | 6$^4$ | | | | | | | | | |
| | | | | | 14 | D Köpfer | 7$^7$ | 7$^7$ | | | | | | | | | |
| | | | | | | | | | | | | | | 3 | F López | 6$^5$ | 3 |
| | | | | | | | | | | | | | | 7 | A Bublik | 7$^7$ | 6 |
| | | | | | 10 | M Krueger | 7$^8$ | 6 | | | | | | | | | |
| | E Escobedo | 6$^5$ | 4 | | Q | K King | 6$^6$ | 3 | | | | | | | | | |
| Q | K King | 7$^7$ | 6 | | | | | | | 10 | M Krueger | 6$^2$ | 3 | | | | |
| | P Krstin | 6 | 6 | | | | | | | 7 | A Bublik | 7$^7$ | 6 | | | | |
| WC | L Gómez | 0 | 3 | | | P Krstin | 6 | 3 | 4 | | | | | | | | |
| | | | | | 7 | A Bublik | 1 | 6 | 6 | | | | | | | | |

### Bottom half
#### Section 3

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 8 | P Polansky | 6 | 6 | | | | | | | | | |
| | Roy Smith | 6$^3$ | 4 | | WC | J Tipsarević | 3 | 2 | | | | | | | | | |
| WC | J Tipsarević | 7$^7$ | 6 | | | | | | | 8 | P Polansky | 7$^7$ | 7$^7$ | | | | |
| | J-P Smith | 6 | 6 | | | | | | | 9 | C Eubanks | 6$^3$ | 6$^4$ | | | | |
| WC | M Sánchez | 4 | 2 | | | J-P Smith | 3 | 7$^7$ | 5 | | | | | | | | |
| | | | | | 9 | C Eubanks | 6 | 6$^3$ | 7 | | | | | | | | |
| | | | | | | | | | | | | | | 8 | P Polansky | 3 | 6$^5$ |
| | | | | | | | | | | | | | | | E Gómez | 6 | 7$^7$ |
| | | | | | 13 | J Ward | 5 | 6$^3$ | | | | | | | | | |
| | G Escobar | 2 | 6 | 5 | | A Pavić | 7 | 7$^7$ | | | | | | | | | |
| | A Pavić | 6 | 2 | 7 | | | | | | | A Pavić | 1 | 0 | | | | |
| | A Collarini | 5 | 2 | | | | | | | | E Gómez | 6 | 6 | | | | |
| | E Gómez | 7 | 6 | | | E Gómez | 6 | 6 | | | | | | | | | |
| | | | | | 4 | C Ruud | 2 | 4 | | | | | | | | | |

#### Section 4

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Third round | Third round | Third round | Third round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals |
| | | | | | 5 | P Lorenzi | 4 | 3 | | | | | | | | | |
| | D Young | 6 | 6 | | | D Young | 6 | 6 | | | | | | | | | |
| | R Ortega Olmedo | 4 | 4 | | | | | | | | D Young | 6 | 6 | | | | |
| | R Cid Subervi | 6$^4$ | 3 | | | | | | | | S Giraldo | 3 | 4 | | | | |
| | S Giraldo | 7$^7$ | 6 | | | S Giraldo | 3 | 7 | 7$^7$ | | | | | | | | |
| | | | | | 11 | R Quiroz | 6 | 5 | 6$^1$ | | | | | | | | |
| | | | | | | | | | | | | | | | D Young | 7 | 6 |
| | | | | | | | | | | | | | | 2 | B Klahn | 5 | 4 |
| | | | | | 15 | S Ofner | 7$^7$ | 1 | 6 | | | | | | | | |
| LL | L Patiño | 1 | 6 | 1 | | V Estrella Burgos | 6$^3$ | 6 | 4 | | | | | | | | |
| | V Estrella Burgos | 6 | 3 | 6 | | | | | | 15 | S Ofner | 3 | 3 | | | | |
| | Evan Song | 2 | 6 | 6 | | | | | | 2 | B Klahn | 6 | 6 | | | | |
| Q | MF Descotte | 6 | 3 | 0 | | E Song | 4 | 3 | | | | | | | | | |
| | | | | | 2 | B Klahn | 6 | 6 | | | | | | | | | |