2021 Emilia-Romagna Open – Men's singles

This was the third edition of the tournament, primarily created due to the one-week delay of the 2021 French Open.

Sebastian Korda won his first ATP Tour singles title, defeating Marco Cecchinato in the final, 6–2, 6–4 without dropping a set. By winning the tournament, Korda became the first American male tennis player to win on European clay since Sam Querrey in 2010.

Seeds
The top four seeds receive a bye into the second round. • # 🇮🇹 Lorenzo Sonego (second round)

• # 🇫🇷 Benoît Paire (second round, retired)

• # 🇪🇸 Albert Ramos Viñolas (second round)

• # 🇩🇪 Jan-Lennard Struff (quarterfinals)

• # 🇫🇷 Richard Gasquet (quarterfinals)

• # 🇺🇸 Tommy Paul (semifinals)

• # Aljaž Bedene (second round)

• # 🇯🇵 Yoshihito Nishioka (quarterfinals)

Seeds
• # 🇸🇰 Norbert Gombos (qualifying competition, lucky loser)

• # 🇦🇺 James Duckworth (first round)

• # 🇪🇸 Pedro Martínez (qualified)

• # 🇸🇪 Mikael Ymer (qualified)

• # 🇫🇷 Benjamin Bonzi (qualifying competition)

• # 🇩🇪 Philipp Kohlschreiber (first round)

• # 🇩🇪 Daniel Altmaier (qualified)

• # 🇮🇹 Matteo Viola (qualifying competition)

Qualifiers
• # 🇩🇪 Daniel Altmaier

• # 🇮🇹 Raúl Brancaccio

• # 🇪🇸 Pedro Martínez

• # 🇸🇪 Mikael Ymer

Lucky loser
• # 🇸🇰 Norbert Gombos