Lin Ye/Yu Mengyu (L) of Singapore compete during a women's doubles quarterfinal match against Gu Yuting/Mu Zi of China at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Cho Daeseong (L)/Shin Yubin of South Korea compete during a mixed doubles quarterfinal match against Ma Te/Wu Yang of China at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Cho Daeseong/Lee Sangsu (front) of South Korea compete during a men's doubles quarterfinal match against Zhao Zihao/Zhu Linfeng of China at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Zhao Zihao (front)/Zhu Linfeng of China compete during a men's doubles quarterfinal match against Cho Daeseong/Lee Sangsu of South Korea at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Gu Yuting (L)/Mu Zi of China compete during a women's doubles quarterfinal match against Lin Ye/Yu Mengyu of Singapore at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Zhao Zihao/Zhu Linfeng (L) of China compete during a men's doubles quarterfinal match against Cho Daeseong/Lee Sangsu of South Korea at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Miu Hirano (L)/Saki Shibata of Japan compete during a women's doubles quarterfinal match against Natalia Bajor/Natalia Partyka of Poland at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Natalia Bajor/Natalia Partyka (L) of Poland compete during a women's doubles match against Miu Hirano/Saki Shibata of Japan at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Gu Yuting/Mu Zi (R) of China compete during a women's doubles quarterfinal match against Lin Ye/Yu Mengyu of Singapore at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Ma Te/Wu Yang (L) of China compete during a mixed doubles quarterfinal match against Cho Daeseong/Shin Yubin of South Korea at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)

Ma Te (R)/Wu Yang of China compete during a mixed doubles quarterfinal match against Cho Daeseong/Shin Yubin of South Korea at the 2019 ITTF Czech Open in Olomouc, the Czech Republic, Aug. 23, 2019. (Xinhua/Shan Yuqi)