Dominika Cibulkova has been ruled out of the Olympics, which begin later this week, after she sustained a left calf injury.
The world number 11 suffered the injury while playing at the Rogers Cup in Montreal last week, where she lost to Eugenie Bouchard in the second round, and was told to rest for seven to 10 days.
The Slovakian, who was set to feature in the singles and doubles events at the Olympics, has won two titles this year – the Katowice Open in April and the Aegon International in June.
Cibulkova is the latest high-profile player to withdraw from the Olympics. Simona Halep and Karolina Pliskova cited concerns over the Zika virus when withdrawing, while Belinda Bencic pulled out as she wants to prepare for the US Open, and Victoria Azarenka was ruled out by her pregnancy.