Maria Sharapova's injury-plagued season continued with the five-time grand slam winner forced to retire in her first match since Wimbledon as she played the Wuhan Open.
The second-seed was down in the deciding set against Czech Barbora Strycova when she was forced to quit at 6-7, 7-6, 1-2.
The setback was only the latest during 2015 for the Russian, who had not played since losing a Wimbledon semi-final on July 9 due to a leg injury.
The 28-year-old was having trouble hitting her backhand as the match went on and did not want to take any chances with the growing problem.
"I've had my fair share of serious injuries, and I know that this is far from it, something that I just have to take care of," the 28-year-old told reporters.
"I mean obviously, Singapore and Fed Cup is a big priority for myself. I'll do everything in order to be healthy for that."
Bouchard pulls out as well
Sharapova was joined on the sidelines of the rich Chinese event by 2014 finalist Eugenie Bouchard, who withdrew before her opening match citing the concussion she suffered earlier this month in a fall in the US Open locker room.
The Wimbledon finalist from last season whose 2015 has been a long downhill slide, pulled the plug on her participation three weeks after slipping and hitting her head in a darkened US Open training room as she walked on a wet floor.
The accident forced the Canadian to forfeit a semi-final against eventual New York finalist Roberta Vinci.
"I travelled to Wuhan with the intention of playing. Unfortunately, my concussion symptoms came back during practice on Saturday and it would not be safe for me to go on court today," Bouchard said in a statement.
"I will rest in Wuhan for the next few days to determine how I progress, and look forward to coming back here to play in this great city next year."
In first-round matches, ninth seed Ana Ivanovic advanced past Alexandra Dulgheru of Romania 6-1, 6-3.
Belinda Bencic started her campaign by defeating Ajla Tomljanovic 7-5, 7-5.