![Yifan Xu and Shuai Zhang of China playing doubles at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Rob Yifan Xu and Shuai Zhang of China playing doubles at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Rob](https://c8.alamy.com/comp/2FA5B11/yifan-xu-and-shuai-zhang-of-china-playing-doubles-at-the-2021-porsche-tennis-grand-prix-wta-500-tournament-on-april-22-2021-at-porsche-arena-in-stuttgart-germany-photo-rob-prange-spain-dppi-dppi-livemedia-2FA5B11.jpg)
Yifan Xu and Shuai Zhang of China playing doubles at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Rob
![Marketa Vondrousova of the Czech Republic during her second-round match at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Marketa Vondrousova of the Czech Republic during her second-round match at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo](https://c8.alamy.com/comp/2FA5A5W/marketa-vondrousova-of-the-czech-republic-during-her-second-round-match-at-the-2021-porsche-tennis-grand-prix-wta-500-tournament-on-april-22-2021-at-porsche-arena-in-stuttgart-germany-photo-rob-prange-spain-dppi-dppi-livemedia-2FA5A5W.jpg)
Marketa Vondrousova of the Czech Republic during her second-round match at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo
![Aryna Sabalenka of Belarus during her second-round match at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Rob Prange / Aryna Sabalenka of Belarus during her second-round match at the 2021 Porsche Tennis Grand Prix, WTA 500 tournament on April 22, 2021 at Porsche Arena in Stuttgart, Germany - Photo Rob Prange /](https://c8.alamy.com/comp/2FA59M6/aryna-sabalenka-of-belarus-during-her-second-round-match-at-the-2021-porsche-tennis-grand-prix-wta-500-tournament-on-april-22-2021-at-porsche-arena-in-stuttgart-germany-photo-rob-prange-spain-dppi-dppi-livemedia-2FA59M6.jpg)