2021 Challenger de Santiago II

Country	Player	Rank1	Seed
ARG	Juan Manuel Cerúndolo	103	1
ARG	Francisco Cerúndolo	110	2
PER	Juan Pablo Varillas	117	3
BOL	Hugo Dellien	140	4
ARG	Sebastián Báez	143	5
CHI	Marcelo Tomás Barrios Vera	155	6
ARG	Juan Ignacio Londero	157	7
BRA	Felipe Meligeni Alves	202	8

• ¹ Rankings are as of 27 September 2021.^[1]

The following players received wildcards into the singles main draw:

• Diego Fernández Flores
• Gonzalo Lama
• Víctor Núñez

The following players received entry into the singles main draw using protected rankings:

• Gerald Melzer
• Gonçalo Oliveira

The following players received entry into the singles main draw as alternates:

• Hernán Casanova
• Lucas Catarina
• Nick Chappell

The following players received entry from the qualifying draw:

• Nicolás Álvarez
• Oliver Crawford
• Facundo Díaz Acosta
• Alexis Gautier

The following player received entry as a lucky loser:

• Cristian Rodríguez

• Juan Pablo Varillas def. Sebastián Báez 6–4, 7–5.

• Diego Hidalgo / Nicolás Jarry def. Evan King / Max Schnur 6–3, 5–7, [10–6].