Aug 31 (Reuters) - Order of play on the main show courts on the third day of the U.S. Open on Wednesday (play starts at 1500 GMT/11 AM ET unless stated, prefix number denotes seeding): ARTHUR ASHE STADIUM (1600 GMT/12 PM ET) Olga Danilovic (Serbia) v 3-Naomi Osaka (Japan) Dominik Koepfer (Germany) v 2-Daniil Medvedev (Russia) Sloane Stephens (U.S.) v 21-Cori Gauff (U.S) Adrian Mannarino (France) v 3-Stefanos Tsitsipas (Greece) LOUIS ARMSTRONG STADIUM Andrea Petkovic (Germany) v 9-Garbine Muguruza (Spain) 18-Victoria Azarenka (Belarus) v Jasmine Paolini (Italy) Frances Tiafoe (U.S.) v Guido Pella (Argentina) Kevin Anderson (South Africa) v 11-Diego Schwartzman (Argentina) 16-Angelique Kerber (Germany) v Anhelina Kalinina (Ukraine)