Results from Day 9 of the Australian Open Grand Slam tennis tournament at Melbourne Park on Tuesday: Men's singles Quarter finals Aslan Karatsev (RUS) bt Grigor Dimitrov (BUL x18) 2-6, 6-4, 6-1, 6-2 Women's singles Quarter finals Naomi Osaka (JPN x3) bt Hsieh Su-wei (TPE) 6-2, 6-2 Serena Williams (USA x10) bt Simona Halep (ROM x2) 6-3, 6-3 afp