210911 -- NEW YORK, Sept. 11, 2021 -- Alexander Zverev of Germany hits a return during the men s singles semifinals of the 2021 US Open between Novak Djokovic of Serbia and Alexander Zverev of Germany in New York, the United States, Sept. 10, 2021. Photo by /Xinhua SPU.S.-NEW YORK-TENNIS-US OPEN-SEMIFINAL-MEN S SINGLES MichaelxNagle PUBLICATIONxNOTxINxCHN