Britain's Katie Swan was forced to retire from her maiden WTA semi-final in Chennai because of illness.
Swan was trailing 3-0 to third seed Magda Linette of Poland after 16 minutes of their match when she called for a medical timeout.
After being assessed by medics, Swan was not well enough to resume.
The British number six had only finished her quarter-final at 3am on Saturday - a match where she also needed a medical timeout.
"I feel bad for Katie," Linette said afterwards. "She gave everything yesterday and it looks like she has paid the price today.