2019 Monterrey Open – Singles

Garbiñe Muguruza was the defending champion and successfully defended her title, after Victoria Azarenka retired in the final with a leg injury with the score at 6–1, 3–1.

Seeds
• #🇩🇪 Angelique Kerber (semifinals)

• #🇪🇸 Garbiñe Muguruza (champion)

• #🇷🇺 Anastasia Pavlyuchenkova (quarterfinals)

• #🇺🇸 Alison Riske (first round)

• #🇧🇾 Victoria Azarenka (final, retired)

• #🇧🇪 Kirsten Flipkens (quarterfinals)

• #🇫🇷 Kristina Mladenovic (quarterfinals)

• #🇸🇰 Magdaléna Rybáriková (semifinals)

Seeds
• # 🇨🇿 Marie Bouzková (first round)

• # 🇺🇸 Christina McHale (first round)

• # 🇷🇴 Monica Niculescu (second round, withdrew)

• # 🇧🇷 Beatriz Haddad Maia (qualified)

• # 🇺🇸 Danielle Lao (second round)

• # 🇨🇳 Lu Jiajing (first round)

• # 🇬🇧 Katie Swan (first round)

• # 🇺🇸 Kristie Ahn (second round)

Qualifiers
• # 🇯🇵 Miyu Kato

• # 🇸🇰 Kristína Kučová

• # 🇨🇳 Xu Shilin

• # 🇧🇷 Beatriz Haddad Maia

Lucky losers
• # 🇭🇺 Gréta Arn

• # 🇷🇴 Elena-Gabriela Ruse