2019 Challenger de Buenos Aires – Singles

Pablo Andújar was the defending champion but chose not to defend his title.

Sumit Nagal won the title after defeating Facundo Bagnis 6–4, 6–2 in the final.

Seeds
All seeds receive a bye into the second round. • # 🇦🇷 Federico Delbonis (second round)

• # 🇧🇴 Hugo Dellien (second round)

• # 🇦🇷 Leonardo Mayer (semifinals)

• # 🇧🇷 Thiago Monteiro (semifinals)

• # 🇦🇷 Guido Andreozzi (third round)

• # 🇦🇷 Federico Coria (second round)

• # 🇮🇳 Sumit Nagal (champion)

• # 🇦🇷 Facundo Bagnis (final)

• # 🇦🇷 Facundo Mena (second round)

• # 🇧🇷 João Menezes (second round)

• # 🇦🇷 Andrea Collarini (quarterfinals)

• # 🇩🇴 José Hernández-Fernández (third round)

• # 🇦🇷 Francisco Cerúndolo (quarterfinals)

• # 🇦🇷 Renzo Olivo (second round)

• # 🇦🇷 Matías Franco Descotte (second round)

• # 🇧🇷 Thiago Seyboth Wild (third round)