2018 Sydney International – Men's singles

Gilles Müller was the defending champion, but lost in the quarterfinals to Benoît Paire.

Daniil Medvedev won his first ATP title, defeating Alex de Minaur in the final, 1–6, 6–4, 7–5.

Seeds
The top four seeds receive a bye into the second round. • #🇪🇸 Albert Ramos Viñolas (second round)

• #🇱🇺 Gilles Müller (quarterfinals)

• #🇦🇷 Diego Schwartzman (second round)

• #🇮🇹 Fabio Fognini (semifinals)

• #🇫🇷 Adrian Mannarino (quarterfinals)

• #🇩🇪 Philipp Kohlschreiber (first round)

• #🇧🇦 Damir Džumhur (second round, retired)

• #🇩🇪 Mischa Zverev (first round)

Seeds
• # 🇷🇺 Daniil Medvedev (qualified)

• # 🇦🇷 Federico Delbonis (first round)

• # 🇷🇺 Evgeny Donskoy (qualified)

• # 🇷🇸 Dušan Lajović (first round)

• # 🇫🇷 Nicolas Mahut (qualifying competition)

• # 🇱🇹 Ričardas Berankis (qualifying competition, lucky loser)

• # 🇨🇿 Václav Šafránek (qualifying competition)

• # 🇷🇺 Teymuraz Gabashvili (qualifying competition, retired)

Qualifiers
• # 🇷🇺 Daniil Medvedev

• # 🇦🇺 Alexei Popyrin

• # 🇷🇺 Evgeny Donskoy

• # 🇦🇺 Aleksandar Vukic

Lucky loser
• # 🇱🇹 Ričardas Berankis