Νέα Υόρκη-22 Αυγούστου 2019: πρωταθλητής του Γκραντ Σλαμ 20 φορές τον Ρότζερ Φέντερερ της Ελβετίας πρακτικές για το 2019 μας Open στο εθνικό κέντρο τένις Μπίλυ Ζαν Κινγκ - Φωτογραφίες & Εικόνες Αρχείου

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, 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, 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, 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, 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, 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, 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 19: Professional tennis player Tomas Berdych practices for US Open 2014 at Billie Jean King National Tennis Center on August 19 , 2014 in New York

NEW YORK - AUGUST 27, 2015: Fourteen times Grand Slam Champion Rafael Nadal of Spain practices for US Open 2015 at Billie Jean King National Tennis Center in New York

FLUSHING, NY - AUGUST 29 Professional tennis player Alexandr Dolgopolov from Ukraine practices for US Open 2013 at Billie Jean King National Tennis Center on August 29, 2013 in Flushing, NY

DELRAY BEACH, FLORIDA - FEBRUARY 18, 2022: Professional tennis player Stefan Kozlov of United States in action during quarter-final match at the 2022 Delray Beach Open tournament in Florida

NEW YORK - AUGUST 24: Professional tennis player Milos Raonic practices for US Open 2014 at Billie Jean King National Tennis Center on August 24 , 2014 in New York

NEW YORK - AUGUST 25: Coach Patrick Mouratoglou supervises sixteen times Grand Slam champion Serena Williams during practice for US Open 2013 at National Tennis Center on August 25 , 2013 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

FLUSHING, NY - AUGUST 19: Seventeen times Grand Slam champion Roger Federer practices for US Open 2013 at Arthur Ashe Stadium at Billie Jean King National Tennis Center on August 19, 2013 in Flushing, NY

NEW YORK - AUGUST 30, 2015: Professional tennis player Tommy Robredo of Spain practices for US Open 2015 at National Tennis Center in New York

FLUSHING, NY - AUGUST 19: Seventeen times Grand Slam champion Roger Federer practices for US Open 2013 at Arthur Ashe Stadium at Billie Jean King National Tennis Center on August 19, 2013 in Flushing, NY

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

MELBOURNE, AUSTRALIA - JANUARY 21, 2019: Professional tennis player Roberto Bautista Agut of Spain in action during his quarter-final match at 2019 Australian Open in Melbourne Park

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