Petra Kvitova defeated Elena Rybakina in the pick of the first-round matches at the Adelaide International 2 on Monday.
Two-time Wimbledon winner Kvitova hit 21 winners to 12 unforced errors on her way to a 6-3 7-5 win against reigning SW19 champion Rybakina in a match lasting 87 minutes.
Belinda Bencic, a defeated finalist in this tournament in 2021, also advanced with a 6-3 6-4 win against former world number one Garbine Muguruza to maintain her positive form.
Fellow seeded players Beatriz Haddad Maia and Danielle Collins beat Sorana Cirstea and Karolina Pliskova respectively to book their places in the last 16.
At the Hobart International, favourite Marie Bouzkova saw off Jacqueline Cristian 7-6 (7-2) 6-3, while Lauren Davis defeated Sloane Stephens 6-2 6-2 in an all-American clash.