Results of matches played on day four of the Brisbane International at the Queensland Tennis Centre on Thursday (X denotes seed): Round two Jennifer Brady (USA) bt Ashleigh Barty (AUS X1) 6-4, 7-6 (7/4) Karolina Pliskova (CZE X2) bt Ajla Tomljanovic (AUS) 6-4, 6-7 (5/7), 6-1 Petra Kvitova (CZE X5) bt Liudmila Samsonova (RUS) 6-3, 6-2 afp