The Australian Open final will be the first meeting between No.4 seed Naomi Osaka and No.8 seed Petra Kvitova, with the winner guaranteed to rise to World No.1 - the second straight year that Melbourne plays host to a new World No.1, but the first time that two players who have never previously been No.1 have met in a Grand Slam final with the top spot on the line. The loser will be World No.2 - still a new career high for Osaka, and the first time Kvitova will have occupied that spot since June 2015.

Petra Kvitova has been on the verge of World No.1 in Australia before: having finished 2011 at No.2, just 115 points behind Caroline Wozniacki, the Czech came within two matches of reaching the summit twice - but lost to Li Na 1-6, 7-5, 6-2 in the Sydney semifinals and Maria Sharapova 6-2, 3-6, 6-4 in the Australian Open semifinals. 28-year-old Kvitova would be the oldest ever first-time World No.1 with a win, while 21-year-old Osaka would be the youngest first-time World No.1 since Wozniacki hit the top in October 2010. Osaka would also be the first ever Asian World No.1, either male or female.

Neither player has lost a Grand Slam final yet: 2011 and 2014 Wimbledon champion Kvitova is 2-0 and 2018 US Open champion Osaka is 1-0. Overall, the Japanese player is 2-2 in finals, while Kvitova is a remarkable 26-7 - including her past eight in a row. The last title match that Kvitova lost was Luxembourg 2016 to Monica Niculescu 6-4, 6-0.

At 21 years and three months old Osaka is the youngest back-to-back Grand Slam finalist since a 20-year-old Ana Ivanovic made the Australian Open final and won Roland Garros in 2008, and is aiming to become the youngest back-to-back major winner since Serena Williams won Wimbledon and the US Open in 2002 as the second and third legs of her first 'Serena Slam'. Since then, the only players other than Williams to win consecutive Slams have been Justine Henin (US Open 2003, Australian Open 2004) and Kim Clijsters (US Open 2010, Australian Open 2011).

Petra Kvitova during her 2012 Australian Open semifinal loss to Maria Sharapova - the last time the Czech was within two matches of taking World No.1 (Getty)

Osaka is the first woman in the Open Era to win her maiden Slam title at the US Open and back it up with a final appearance at the subsequent Australian Open. She is also the first maiden Slam champion to also reach the final in her next major since Jennifer Capriati, who won the Australian Open and Roland Garros in 2001.

This time last year, Osaka was titleless and ranked World No.72 - having backslid from her 2016 year-end ranking of World No.40 - and entered the Australian Open having lost seven of her previous nine matches. Her run to the fourth round was her first ever appearance in the second week of a major. Meanwhile, Kvitova was ranked World No.28 and won just one match over the Australian swing, crashing out in the first round of Melbourne in a torrid 6-3, 4-6, 10-8 epic to Andrea Petkovic.

Kvitova has spent seven hours and five minutes on court so far, conceding no sets and just 28 games en route to the final - the lowest number since Serena Williams made the 2016 final dropping 26 games. Williams was also the last player to win the Australian Open without dropping a set, in 2017. Danielle Collins has managed to keep Kvitova on court the longest so far in their one-hour, 34-minute semifinal; the lengths of Kvitova's other five matches were in a 10-minute range, with the Czech finishing them all between 59 and 69 minutes.

By contrast, Osaka has spent eight hours and 51 minutes on court and dropped three sets, to Hsieh Su-Wei - against whom she trailed 5-7, 2-4, 0-40 - in the third round, Anastasija Sevastova in the fourth round and Karolina Pliskova in the semifinals. However, the highest-ranked opponent Kvitova has faced this fortnight is World No.15 Ashleigh Barty in the quarterfinals. Osaka has played three opponents ranked above that: World No.12 Sevastova, World No.8 Pliskova and World No.7 Elina Svitolina. Each is the first Slam champion that the other has faced.

Naomi Osaka during her 2016 Tianjin quarterfinal loss to Svetlana Kuznetsova - the last time the Japanese player lost a match after winning the first set (Getty)

Osaka tops the Australian Open ace leaderboard with a total of 50 so far, alongside 226 winners - 15.06 per set. Kvitova has tallied 26 aces and 157 winners (13.08 per set) this fortnight.

Osaka is on a 59-match winning streak after taking the first set of a match - the best active such streak on Tour, tying Serena Williams (Berlin 2002 to Rome 2003), Wendy Turnbull (Eastbourne 1981 to the 1982 Australian Open) and Martina Navratilova (Eastbourne 1986 to Houston 1987). Osaka's last loss from a set up was in October 2016 in the Tianjin quarterfinals to Svetlana Kuznetsova 2-6, 6-4, 7-6(3). Both players are unbeaten over three sets this year so far, with Osaka going 4-0 and Kvitova 2-0.

The girls' final pits two 16-year-olds against each other, No.1 seed Clara Tauson and No.4 seed Leylah Fernandez - a rematch of last week's Grade 1 final in Traralgon, won 6-3, 6-2 by Tauson, who also leads the overall head-to-head 2-1. Tauson, who won her first ITF W15 pro title in Stockholm in 2017, is aiming to become the first Danish junior Slam champion since Caroline Wozniacki at Wimbledon 2006; Fernandez, who won her first WTA main draw match in Québec City last year and is ranked World No.434, is bidding to become the first Canadian junior Slam champion since Eugenie Bouchard at Wimbledon 2012.



Naomi Osaka has credited the work she put in on her fitness during the off-season for her confidence this year; her fitness coach, Abdul Sillah, has now worked with three players (formerly Serena Williams and Sloane Stephens) en route to a Grand Slam title, and tells Reem Abulleil in an interview for Sport360 that his goal had been to turn Osaka into a "sprinter".

In a panel discussion for SI.com, Jon Wertheim, Stanley Kay, Jamie Lisanti, Daniel Rapaport and Tristan Jung break down each finalists' strengths and weaknesses - and, zooming further out, analyse why each of their runs this fortnight is so impressive.

Elsewhere, former World No.1 and Australian Open champion Amélie Mauresmo has coached Lucas Pouille to the men's semifinals in their first Grand Slam together - while Conchita Martínez and Rennae Stubbs co-coached Karolina Pliskova to the same stage of the women's event. Reem Abulleil explores the growing prominence of female coaches for ausopen.com.


Click here for the second Saturday's order of play at Flinders Park.