Fastest ascent to WTA No.1 ranking following Top 10 debut

It took Naomi Osaka (Japan) just 20 weeks to climb to the top of the WTA (Women’s Tennis Association) world rankings after making her debut as a Top 10 player on 10 September 2018. Osaka’s rapid rise to the top of the women’s game saw her win back-to-back Grand Slam titles – at the US Open on 8 September 2018 and the Australian Open on 26 January 2019. Two days after her 7-6, 5-7, 6-4 victory against Petra Kvitova in the Melbourne Park final, Osaka was confirmed as the new world number one – replacing Simona Halep – when the WTA published its latest rankings list.

As confirmed by the WTA on 10 September 2018, Osaka (b. 16 October 1997) rose from No.12 to No.7 in the world after defeating an ill-tempered Serena Williams 6-2, 6-4 in the Flushing Meadows final two days previously, aged 20 years 327 days.

Osaka was confirmed as the world’s top-ranked female singles player on 28 January 2019, aged 21 years 104 days, climbing from No.4 the previous week. Kvitova, who herself would have taken the No.1 ranking had she won the Australian Open final, rose to No.2 in the world from her previous week’s ranking of No.6.

Osaka’s 20-week rise from Top 10 to No.1 beat the previous fastest ascent to the top of the WTA’s world rankings, 25 weeks, by both Evonne Goolagong Cawley (3 November 1975 to 26 April 1976) and Martina Hingis (7 October 1996 to 31 March 1997). A total of 26 women have been world number one since the introduction of computerized rankings on 3 November 1975.

By winning the 2018 US Open, Osaka became the first Japanese player – male or female – to win a Grand Slam singles title. By winning the 2019 Australian Open, she became the first female player to win back-to-back Slams since Serena Williams in 2015, and the first player – male or female – since Jennifer Capriati in 2001 to win a second Slam immediately after their first. (John Newcombe, in pre-open-era 1967, was the last man to win a second Slam straight after his first.) Osaka also became the first Asian player – male or female – to be ranked world number one.

Osaka won her maiden WTA Tour title – and her first title at any level of tennis – at the Indian Wells Open (aka the BNP Paribas Open) in California, USA, on 18 March 2018, following it up with her first Grand Slam title, at Flushing Meadows in New York, just 174 days later.

As of 11 February 2019, Osaka had secured a third week as world number one with 7,030 ranking points, ahead of Kvitova (5,920 points) and Halep (5,582).