New York - augustus 22, 2018: 13-tijd Grand Slam champion Novak Djokovic van Servië voor de 2018 Us Open op Billie Jean King National Tennis praktijken - Stockfoto’s en -afbeeldingen

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: American retired professional tennis player James Blake in action during 2018 US Open exhibition match at newly open Louis Armstrong Stadium at National Tennis Center

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK- SEPTEMBER 3, 2016: Twelve times Grand Slam champion Novak Djokovic of Serbia practices for for US Open 2016 at Billie Jean King National Tennis Center in New York

NEW YORK - AUGUST 22, 2019: 20-time Grand Slam champion Roger Federer of Switzerland practices for the 2019 US Open at Billie Jean King National Tennis Center

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - SEPTEMBER 4, 2016: Professional tennis player Jack Sock of United States in action during his round four match at US Open 2016 at Billie Jean King National Tennis Center in New York

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - SEPTEMBER 5, 2016: Professional tennis player Ivo Karlovic of Croatia in action during US Open 2016 round four match at Billie Jean King National Tennis Center

NEW YORK - AUGUST 22, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia practices for the 2018 US Open at Billie Jean King National Tennis

NEW YORK - SEPTEMBER 3, 2018: 13-time Grand Slam champion Novak Djokovic of Serbia in action during his 2018 US Open round of 16 match at Billie Jean King National Tennis Center