Results on day four of the Australian Open Grand Slam at Melbourne Park on Thursday (x denotes seeding): Men's singles 2nd rd Gael Monfils (FRA x10) bt Ivo Karlovic (CRO) 4-6, 7-6 (10/8), 6-4, 7-5 Ernests Gulbis (LAT) bt Aljaz Bedene (SLO) 7-5, 6-3, 6-2 Dominic Thiem (AUT x5) bt Alex Bolt (AUS) 6-2, 5-7, 6-7 (5/7), 6-1, 6-2 Daniil Medvedev (RUS x4) bt Pedro Martinez (ESP) 7-5, 6-1, 6-3 Alexei Popyrin (AUS) bt Jaume Munar (ESP) 6-2, 7-6 (7/5), 6-2 John Isner (USA x19) bt Alejandro Tabilo (CHI) 6-4, 6-3, 6-3 Andrey Rublev (RUS x17) bt Yuichi Sugita (JPN) 6-2, 6-3, 7-6 (7/5) Alexander Zverev (GER x7) bt Egor Gerasimov (BLR) 7-6 (7/5), 6-4, 7-5 Women's singles 2nd rd Belinda Bencic (SUI x6) bt Jelena Ostapenko (LAT) 7-5, 7-5 Anett Kontaveit (EST x28) bt Sara Sorribes (ESP) 6-2, 4-6, 6-1 Donna Vekic (CRO x19) bt Alize Cornet (FRA) 6-4, 6-2 Iga Swiatek (POL) bt Carla Suarez (ESP) 6-3, 7-5 Elise Mertens (BEL x16) bt Heather Watson (GBR) 6-3, 6-0 Catherine Bellis (USA) bt Karolina Muchova (CZE x20) 6-4, 6-4 Garbine Muguruza (ESP) bt Ajla Tomljanovic (AUS) 6-3, 3-6, 6-3 Zarina Diyas (KAZ) bt Anna Blinkova (RUS) 4-6, 6-3, 6-4 Kiki Bertens (NED x9) bt Arina Rodionova (AUS) 6-3, 7-5 Angelique Kerber (GER x17) bt Priscilla Hon (AUS) 6-3, 6-2 Anastasia Pavlyuchenkova (RUS x30) bt Taylor Townsend (USA) 7-5, 7-6 (7/1) Karolina Pliskova (CZE x2) bt Laura Siegemund (GER) 6-3, 6-3 afp