Naomi Osaka, winner of the Australian Open, has jumped to the top of women's tennis with her beaten opponent Petra Kvitova rising to second in Monday's Women's Tennis Association (WTA) rankings.

Osaka climbed three places after beating the Czech in Melbourne on Saturday. Kvitova moved up four places.

The 21-year-old Japanese player has only won three career titles, but those include the last two majors, after she won the US Open in September.

Romanian former number one Simona Halep, knocked out by Serena Williams in the round of 16 in Melbourne, fell two spots to third. Dane Caroline Wozniacki, whose defence of her Australian Open title ended in the third round, fell six places to ninth.

The biggest rise of the week was by the 25-year-old American Danielle Collins who leaped 12 places to 23rd after her run to the semi-finals.

The other semi-finalist, Czech Karolina Pliskova, who saved four match points against Williams in their quarterfinal, also advanced, gaining three places to fifth in the world.

Williams, who fell to 491 after her maternity break last year, continued her rise, gaining five places to 11th.

WTA rankings: 1. Naomi Osaka (JPN) 7,030 pts (+3) 2. Petra Kvitova (CZE) 6,290 (+4) 3. Simona Halep (ROM) 5,582 (-2) 4. Sloane Stephens (USA) 5,307 (+1) 5. Karolina Pliskova (CZE) 5,100 (+3) 6. Angelique Kerber (GER) 4,965 (-4) 7. Elina Svitolina (UKR) 4,940 8. Kiki Bertens (NED) 4,430 (+1) 9. Caroline Wozniacki (DEN) 3,566 (-6) 10. Aryna Sabalenka (BLR) 3,485 (+1) 11. Serena Williams (USA) 3,406 (+5) 12. Darya Kasatkina (RUS) 3,355 (-2) 13. Anastasija Sevastova (LAT) 3,330 (-1) 14. Ashleigh Barty (AUS) 3,285 (+1) 15. Garbine Muguruza (ESP) 3,035 (+3) 16. Julia Goerges (GER) 2,995 (-3) 17. Madison Keys (USA) 2,786 18. Wang Kiang (CHN) 2,605 (+3) 19. Caroline Garcia (FRA) 2,550 20. Anett Kontaveit (EST) 2,355