U.S. Open champion Naomi Osaka has reached back-to-back major finals with a 6-2, 4-6, 6-4 victory over Karolina Pliskova in the Australian Open semifinals. The 21-year-old Osaka will play another Czech, two-time Wimbledon champion Petra Kvitova, for the Australian title on Saturday. The champion in Australia will also assume the No.