Bulgaria's Grigor Dimitrov hits a return to Japan's Kei Nishikori during Rome's ATP Tennis Open tournament at the Foro Italico, on May 16, 2018 in Rome. (Photo by Andreas SOLARO / AFP) (Photo credit should read ANDREAS SOLARO/AFP/Getty Images)
Bulgaria's Grigor Dimitrov hits a return to Japan's Kei Nishikori during Rome's ATP Tennis Open tournament at the Foro Italico, on May 16, 2018 in Rome. (Photo by Andreas SOLARO / AFP) (Photo credit should read ANDREAS SOLARO/AFP/Getty Images)