Japan’s Naomi Osaka overcame a spirited challenge from two-time Wimbledon champion Petra Kvitova to claim the Australian Open title with a 7-6(2) 5-7 6-4 win on Saturday.

It was a second successive Grand Slam crown for Osaka, after her U.S. Open triumph in September.

Kvitova saved four match points, showing the same resilience she needed to return to the top level of tennis after a knife attack and lengthy surgery in 2016, but her fightback fell just short.

Osaka, who replaces Simona Halep at the top of the rankings after the Romanian’s 48-week stint, becomes the first Asian player to be world number one.

She is also the youngest to hold top spot since Denmark’s Caroline Wozniacki, then aged 20, took the ranking in 2010.

The 21-year-old is also the first player since Jennifer Capriati in 2001 to win the next Grand Slam after her maiden major title.