Highlights of 2019 Wimbledon Tennis Championships day 7

(190709) -- LONDON, July 9, 2019 (Xinhua) -- Kei Nishikori returns the ball during the men's singles fourth round match between Kei Nishikori of Japan and Mikhail Kukushkin of Kazakhstan at the 2019 Wimbledon Tennis Championships in London, Britain, on July 8, 2019. (Xinhua/Lu Yang)