2013 Rakuten Japan Open Tennis Championships – Singles

Kei Nishikori was the defending champion, but lost in the quarter-finals to Nicolás Almagro. First-seeded Juan Martín del Potro won the title, defeating Milos Raonic in the final, 7–6(7–5), 7–5.

Seeds
• # 🇦🇷 Juan Martín del Potro (champion)

• # 🇫🇷 Jo-Wilfried Tsonga (second round)

• # 🇨🇦 Milos Raonic (final)

• # 🇯🇵 Kei Nishikori (quarterfinals)

• # 🇫🇷 Gilles Simon (withdrew)

• # 🇪🇸 Nicolás Almagro (semifinals)

• # Kevin Anderson (first round)

• # 🇷🇸 Janko Tipsarević (second round)

Seeds
• # 🇦🇷 Federico Delbonis (first round)

• # 🇫🇷 Édouard Roger-Vasselin (qualified)

• # 🇩🇪 Benjamin Becker (qualified)

• # Grega Žemlja (first round, retired)

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

• # 🇵🇱 Michał Przysiężny (qualifying competition, lucky loser)

• # 🇨🇴 Alejandro Falla (qualifying competition)

• # 🇺🇸 Michael Russell (qualifying competition)

Qualifiers
• # Marco Chiudinelli

• # 🇫🇷 Édouard Roger-Vasselin

• # 🇩🇪 Benjamin Becker

• # 🇺🇸 Ryan Harrison

Lucky losers
• # 🇸🇰 Lukáš Lacko

• # 🇵🇱 Michał Przysiężny