World number two Simona Halep has withdrawn from the Stuttgart Open with a hip injury.
The 27-year-old suffered the injury during her win over Caroline Garcia in Romania's Fed Cup defeat by France on Sunday.
Halep is however hopeful to be fit for next month's tournaments in Madrid and Rome before defending her French Open title from May 26.
"If I'm not 100 per cent , I don't want to step on the court," Halep said.
"I'm also exhausted mentally because I gave my everything in that tie but unfortunately we couldn't win.
"That's why I decided to pull out, because I have to think about my health first.
"I've been very sad the last two days. I've been through these moments many times, so I know how to handle it. I just need to recover mentally and physically and then just start again."
Spain's world number 19 Garbine Muguruza has also pulled out of the Stuttgart Open through illness.