2011 Natomas Men's Professional Tennis Tournament – Singles

John Millman was the defending champion, but did not participate. Ivo Karlović won the title, defeating James Blake 6–4, 3–6, 6–4 in the final.

Seeds
• # 🇺🇸 James Blake (final)

• # Ivo Karlović (champion)

• # 🇺🇸 Sam Querrey (semifinals)

• # 🇺🇸 Bobby Reynolds (quarterfinals)

• # 🇨🇦 Vasek Pospisil (first round)

• # Izak van der Merwe (second round)

• # 🇩🇪 Björn Phau (second round)

• # 🇬🇧 James Ward (first round)