Stan Wawrinka of Switzerland hits a return to Juan Monaco of Argentina during the ATP Tennis Open tournament at the Foro Italico, on May 12, 2015 in Rome. AFP PHOTO / ANDREAS SOLARO (Photo credit should read ANDREAS SOLARO/AFP/Getty Images)
Stan Wawrinka of Switzerland hits a return to Juan Monaco of Argentina during the ATP Tennis Open tournament at the Foro Italico, on May 12, 2015 in Rome. AFP PHOTO / ANDREAS SOLARO (Photo credit should read ANDREAS SOLARO/AFP/Getty Images)