Novak Djokovic (Front) of Serbia and Kevin Anderson of South Africa compete during the quarterfinal match of men's doubles against Nikola Mektic of Croatia and Alexander Peya of Austria at the 2018 Rogers Cup in Toronto, Canada, Aug. 10, 2018. Novak Djokovic of Serbia and Kevin Anderson of South Africa lost 0-2. (Xinhua/Zou Zheng)?