PRAGUE, CZECH REPUBLIC - SEPTEMBER 24: US John Isner of the Team World in action against Spanish Rafael Nadal (not seen) of the Team Europe during the Laver Cup in Prague, Czech Republic on September 24, 2017. It is a three day (22 to 24 September 2017) tournament pitting a team of the six best tennis players from Europe against six opponents from the rest of the world. The tournament has been named in honor of Australian tennis legend Rod Laver. At the beginning of the exhibition project was a tennis player Roger Federer, whose company TEAM8 is the main owner of the competition. (Photo by Lukas Kabon/Anadolu Agency/Getty Images)
