2011 U.S. Men's Clay Court Championships – Singles

Juan Ignacio Chela was the defending champion, but could not defend his title since he withdrew from the tournament for personal reasons.

Ryan Sweeting claimed the title, defeating Kei Nishikori 6–4, 7–6(7–3) in the final match.

Seeds
The top four seeds received a bye into the second round. • # 🇺🇸 Mardy Fish (quarterfinals)

• # 🇺🇸 Sam Querrey (second round)

• # 🇪🇸 Guillermo García López (quarterfinals)

• # 🇺🇸 John Isner (quarterfinals)

• # 🇩🇪 Benjamin Becker (first round)

• # 🇯🇵 Kei Nishikori (final)

• # Pablo Cuevas (semifinals)

• # 🇧🇬 Grigor Dimitrov (second round)