2021 Estoril Open – Singles

Albert Ramos Viñolas defeated Cameron Norrie in the final, 4–6, 6–3, 7–6(7–3) to win the singles tennis title at the 2021 Estoril Open. It marked his third career ATP Tour singles title, all of which have been on clay. Norrie was aiming to win his first ATP Tour title in his second final.

Stefanos Tsitsipas was the defending champion from when the tournament was last held in 2019, but did not return to compete.

Seeds
The top four seeds received a bye into the second round. • #🇨🇦 Denis Shapovalov (second round)

• # Cristian Garín (quarterfinals)

• #🇫🇷 Ugo Humbert (quarterfinals)

• #🇯🇵 Kei Nishikori (withdrew)

• #🇰🇿 Alexander Bublik (first round)

• # Marin Čilić (semifinals)

• #🇪🇸 Albert Ramos Viñolas (champion)

• #🇪🇸 Alejandro Davidovich Fokina (semifinals)

Seeds
• # 🇪🇸 Jaume Munar (qualified)

• # 🇪🇸 Roberto Carballés Baena (qualifying competition, lucky loser)

• # 🇦🇷 Juan Ignacio Londero (moved to main draw)

• # 🇪🇸 Pedro Martínez (qualified)

• # Pedro Sousa (first round)

• # 🇪🇸 Carlos Alcaraz (qualified)

• # 🇺🇸 Brandon Nakashima (first round)

• # 🇬🇧 Liam Broady (first round)

Qualifiers
• # 🇪🇸 Jaume Munar

• # Nuno Borges

• # 🇪🇸 Carlos Alcaraz

• # 🇪🇸 Pedro Martínez

Lucky loser
• # 🇪🇸 Roberto Carballés Baena