2021 Aberto da República

Country	Player	Rank1	Seed
ARG	Federico Coria	69	1
ESP	Jaume Munar	83	2
ARG	Sebastián Báez	111	3
ARG	Francisco Cerúndolo	112	4
BOL	Hugo Dellien	120	5
ARG	Tomás Martín Etcheverry	129	6
BRA	Thiago Seyboth Wild	132	7
ARG	Juan Ignacio Londero	144	8

• ¹ Rankings are as of 15 November 2021.

The following players received wildcards into the singles main draw:

• Mateus Alves
• Gustavo Heide
• Wilson Leite

The following player received entry into the singles main draw as an alternate:

• Alejandro González

The following players received entry from the qualifying draw:

• Bogdan Bobrov
• Luciano Darderi
• Alejandro Gómez
• Tomás Lipovšek Puches

The following player received entry as a lucky loser:

• José Pereira

Country	Player	Rank1	Seed
HUN	Panna Udvardy	115	1
PAR	Verónica Cepede Royg	208	2
BRA	Laura Pigossi	218	3
ROU	Gabriela Lee	229	4
BRA	Carolina Alves	258	5
RUS	Elina Avanesyan	261	6
ARG	María Lourdes Carlé	262	7
CHN	You Xiaodi	265	8

• ¹ Rankings are as of 15 November 2021.

The following players received wildcards into the singles main draw:

• Ana Candiotto
• Sofia da Cruz Mendonça
• Júlia Klimovicz
• Maria Luisa Oliveira

The following players received entry using protected rankings:

• Thaísa Grana Pedretti
• Olivia Tjandramulia

The following players received entry from the qualifying draw:

• Martina Capurro Taborda
• Lara Escauriza
• Merel Hoedt
• Jasmin Jebawy
• Katarina Jokić
• Sabastiani León
• Luisa Meyer auf der Heide
• Emily Welker

The following players received entry as lucky losers:

• Maria Lota Kaul
• Noelia Zeballos

• Federico Coria def. Jaume Munar 7–5, 6–3.

• Panna Udvardy def. Elina Avanesyan, 0–6, 6–4, 6–3

• Mateus Alves / Gustavo Heide def. Luciano Darderi / Genaro Alberto Olivieri 6–3, 6–3.

• Carolina Alves / María Lourdes Carlé def. Valeriya Strakhova / Olivia Tjandramulia 6–2, 6–1