BEIJING - China's home favorite Peng Shuai retired on Thursday due to a knee injury while trailing 3-0 in the first set against Jelena Ostapenko of Latvia here at 2017 China Open third round.

Peng Shuai reacts during a post-game conference at the 2017 China Open in Beijing October 5, 2017.?[Photo/Agencies]

"Maybe recently there were ups and downs and several matches in a row that stressed it (knee injury)," Peng Shuai said, "The doctor suggested I should take a period of rest and get it treated, but I can only rest after the season. I won't retire from tomorrow's doubles."

Ostapenko, the reigning French Open champion, enjoyed a good start and stormed to a 3-0 lead before Peng calling for the timeout to deal with her injury.

"It's not the result I wanted to have. I feel bad for Shuai, and hopefully she can recover and will be fine." the Latvian said after the match.

It's the first time Ostapenko advances to the quarterfinals of the China Open, where she will face Sorana Cirstea of Romania, her doubles partner this time.