Novak Djokovic beats Kei Nishikori 3-0 at 2018 US Open tennis tournament

Kei Nishikori of Japan hits a return during the men's singles semifinal match against Novak Djokovic of Serbia at the 2018 US Open tennis tournament in New York, the United States, Sept. 7, 2018. Novak Djokovic won 3-0. (Xinhua/Liu Jie)