Dominika Cibulkova has been forced to withdraw from the Stuttgart Open due to a wrist injury.
The world number four confirmed the news on Monday, with the main-draw action set to begin on Tuesday.
"I always look forward to playing this event and I am very disappointed that my health will not allow me to play this year," said Cibulkova.
"I hope to come back and play for the fans in Stuttgart next year."
Cibulkova's spot will be taken by Garbine Muguruza, with a qualifier or lucky loser to replace the French Open champion.
This week's WTA Premier event sees the return of Maria Sharapova to the Tour after the Russian served her 15-month suspension for a doping violation.