2018 Monterrey Challenger

Country	Player	Rank1	Seed
ESP	Marcel Granollers	104	1
USA	Michael Mmoh	108	2
ITA	Paolo Lorenzi	113	3
ESP	Adrián Menéndez Maceiras	121	4
CRO	Ivo Karlović	137	5
ESP	David Ferrer	149	6
AUT	Gerald Melzer	153	7
ESP	Pedro Martínez	174	8

• ¹ Rankings are as of 24 September 2018.^[1]

The following players received wildcards into the singles main draw:

• Víctor Estrella Burgos
• Lucas Gómez
• Gerardo López Villaseñor
• Jürgen Melzer

The following player received entry into the singles main draw using a protected ranking:

• Santiago Giraldo

The following players received entry from the qualifying draw:

• Harrison Adams
• Gonzalo Escobar
• Pavel Krainik
• Zsombor Piros

The following player received entry as a lucky loser:

• Sekou Bangoura

• David Ferrer def. Ivo Karlović 6–3, 6–4.

• Marcelo Arévalo / Jeevan Nedunchezhiyan def. Leander Paes / Miguel Ángel Reyes-Varela 6–1, 6–4.