2018 ASB Classic – Men's singles

Jack Sock was the defending champion, but lost in the second round to Peter Gojowczyk.

Roberto Bautista Agut won the title, defeating Juan Martín del Potro in the final, 6–1, 4–6, 7–5.

Seeds
The top four seeds received a bye into the second round. • # 🇺🇸 Jack Sock (second round)

• # 🇦🇷 Juan Martín del Potro (final)

• # 🇺🇸 Sam Querrey (second round)

• # 🇺🇸 John Isner (second round)

• # 🇪🇸 Roberto Bautista Agut (champion)

• # Pablo Cuevas (second round)

• # 🇪🇸 David Ferrer (semifinals)

• # 🇷🇺 Andrey Rublev (withdrew)

Seeds
• #🇲🇩 Radu Albot (qualified)

• #🇸🇰 Lukáš Lacko (qualifying competition, lucky loser)

• #🇺🇸 Tennys Sandgren (qualifying competition, lucky loser)

• # Blaž Kavčič (first round)

• #🇯🇵 Taro Daniel (qualifying competition, lucky loser)

• #🇧🇷 Rogério Dutra Silva (qualified)

• #🇺🇸 Tim Smyczek (qualified)

• #🇳🇴 Casper Ruud (qualified)

Qualifiers
• # 🇲🇩 Radu Albot

• # 🇧🇷 Rogério Dutra Silva

• # 🇳🇴 Casper Ruud

• # 🇺🇸 Tim Smyczek

Lucky losers
• # 🇸🇰 Lukáš Lacko

• # 🇺🇸 Tennys Sandgren

• # 🇯🇵 Taro Daniel

• # 🇮🇹 Liam Caruana