Naomi Osaka of Japan, beaten by Pliskova in a marathon semi-final at Brisbane, moves up one place to third at the expense of Simona Halep, who is also fine-tuning her Australian Open challenge in Adelaide.
Serena Williams, who ended a three-year title drought with victory in Sunday’s Auckland Classic final, also moves up one place to ninth.
WTA rankings on January 13:
1. Ashleigh Barty (AUS) 7,547 pts
2. Karolina Pliskova (CZE) 5,940
3. Naomi Osaka (JPN) 5,496 (+1)
4. Simona Halep (ROU) 5,461 (-1)
5. Elina Svitolina (UKR) 5,075
6. Bianca Andreescu (CAN) 4,935
7. Belinda Bencic (SUI) 4,605 (+1)
8. Petra Kvitova (CZE) 4,436 (-1)
9. Serena Williams (USA) 4,215 (+1)
10. Kiki Bertens (NED) 4,165 (-1)
11. Madison Keys (USA) 3,072 (+2)
12. Aryna Sabalenka (BLR) 2,940 (-1)
13. Johanna Konta (GBR) 2,813 (-1)
14. Petra Martic (CRO) 2,646 (+1)
15. Sofia Kenin (USA) 2,565 (-1)
16. Marketa Vondrousova (CZE) 2,390
17. Elise Mertens (BEL) 2,250
18. Angelique Kerber (GER) 2,175
19. Alison Riske (USA) 2,130
20. Donna Vekic (CRO) 2,080
