World number one Ash Barty ended her Australian Open preparations with a title after defeating Garbine Muguruza in the Yarra Valley Classic final.

Barty – gearing up for the year's first grand slam which gets underway in Melbourne on Monday – defeated sixth seed and 2020 Australian Open runner-up Muguruza 7-6 (7-3) 6-4 on Sunday.

Looking to add to her 2019 French Open crown, Australian star Barty claimed her ninth WTA Tour trophy and second on home soil.

"It was some of the better tennis I played throughout the whole week," Barty, who had not played in a competitive tournament since last February, told reporters in her post-match news conference.

"Garbine forced me to play at that level. It was a great final."

Barty added: "Overall it was a pretty solid performance. I'm still my harshest critic at times. That's the challenge of sport every day, is trying to get better and better."

Elsewhere in Melbourne, Elise Mertens clinched the Gippsland Trophy with a 6-4 6-1 win over Estonian veteran Kaia Kanepi.

Mertens – the seventh-seeded Belgian – returned to the winner's circle following two runner-up finishes in 2020.

As for Anett Kontaveit and Ann Li, they shared the Grampians Trophy on Sunday.

The Grampians Trophy did not have a final, the WTA announced, due to time running out before the Australian Open begins. Thursday's play was cancelled as a precautionary measure after a case of coronavirus involving a worker from a hotel that had housed quarantining tennis stars.

Kontaveit outlasted fifth seed Maria Sakkari 2-6 6-3 11-9 in the first semi-final, while Li upset seventh seed Jennifer Brady 7-6 (7-5) 6-7 (5-7) 10-6.

Serena Williams has withdrawn from her semi-final at the Yarra Valley Classic due to an injury to her right shoulder.

As a result, home favourite Ash Barty will progress to the final of the Australian Open warm-up event at Melbourne Park.

Williams, who is chasing an eighth Australian Open crown and an historic 24th grand slam singles success, had been in impressive form this week, demolishing Tsvetana Pironkova in straight sets.

Friday's quarter-final against American Danielle Collins proved a harder slog, as she was forced into a match tiebreak to win 6-2 4-6 10-6.

An anticipated showdown against Barty will now not come to pass, with the world number one to pursue a ninth career title against either Garbine Muguruza or Marketa Vondrousova.

"I think the rust is always there for everyone the first few matches of the season. But without a doubt, I felt better and better each match," Barty told reporters after being taken the distance by Shelby Rodgers.

"Each match has been very different, different challenges, different things I've had to overcome, which is the best thing, to be able to work through those and give myself another chance to play a little bit better the next day, focus on some new challenges for the next day."

Williams is due to face Germany's Laura Siegemund in the first round of the Australian Open on Monday.

Australian Open champion Novak Djokovic could face Dominic Thiem in a mouth-watering semi-final after being handed a tough path to success at Melbourne Park, where Serena Williams will continue her quest for a 24th grand slam singles title.

The Australian Open draw took place on Friday, with world number one Djokovic set to play Frenchman Jeremy Chardy in the opening round of the year's first major tournament.

Amid coronavirus concerns in Melbourne, where Swiss great Roger Federer is absent, Djokovic has set his sights on a ninth crown and 18th major success, but the top seed's title defence is far from straightforward.

Djokovic could face Gael Monfils (fourth round) and sixth seed Alexander Zverev (quarter-final) en route to a possible semi-final against US Open champion and third seed Thiem.

The Serb overcame Thiem in a five-set thriller in last year's Australian Open final, before the latter broke through for his maiden major trophy at Flushing Meadows.

Djokovic could then meet second seed and 20-time major champion Rafael Nadal in a blockbuster final – he blitzed the Spanish superstar in the 2019 Australian Open decider but lost in three one-sided sets in their previous meeting in the French Open final.

Nadal will go head-to-head with another Serb in the first round – Laslo Djere – while Stefanos Tsitsipas could await in the quarters, with 2019 US Open final opponent Daniil Medvedev also on the same side of the draw.

Meanwhile, Williams' bid for a record-equalling 24th slam will begin against German Laura Siegemund.

The 39-year-old Williams has been stuck on 23 majors since winning the Australian Open in 2017 – losing finals at Wimbledon (2018 and 2019) and the US Open (2018 and 2019).

World number one and local hope Ashleigh Barty will meet Montenegro's Danka Kovinic in round one and defending champion Sofia Kenin faces Australian wildcard Maddison Inglis.

The last 16 could see Williams clash with Aryna Sabalenka, Barty meet Petra Martic, Kenin tackle Johanna Konta and three-time major champion Naomi Osaka do battle with last year's runner-up Garbine Muguruza.

One in eight women in the Australian Open draw have already won a grand slam title.

One in eight. It is staggering that of the 128 players who set out in the hope of singles glory at Melbourne Park, there are 16 major champions among them, and perhaps never has it been so difficult to predict who will carry off the title.

Compare it to the men's draw, where there are just five grand slam singles winners, and where you would struggle to make a compelling case for any more than three of those this year, with apologies to Stan Wawrinka and Marin Cilic.

As long-running dynasties near their end on the men's and women's tours, the WTA is a lengthy step ahead of the ATP with a cast of appealing characters already assuming leading roles.

The leader of the pack

Three-time grand slam champion Naomi Osaka is at the forefront of a school of rising stars, but she has impressive rivals for company.

The last four years have seen the 15 women's majors won by 12 different players, whereas in the men's game, Rafael Nadal (6), Novak Djokovic (5), Roger Federer (3) and Dominic Thiem (1) have creamed off all the top prizes in the same period.

Often criticised in the past for a perceived lack of depth, in the years when Serena Williams won seemingly at will, the women's tour has exploded with a rush of bright and young talent.

Osaka is a revelation and a leader, on and off the court. Twice a US Open champion now, and a winner in Australia two years ago, the 23-year-old Japanese star took a powerful stance for racial equality at Flushing Meadows back in September, at the height of Black Lives Matter protests. She wants to achieve even more off the court than on it, where she looks assured of one day leaving an impressive legacy.

If there is any area where Osaka's game falls down it is consistency. She has surprisingly not passed the fourth round in 14 of her 17 grand slam appearances, but on every occasion she has gone beyond that stage it has been en route to lifting a trophy.

In hot pursuit

Last year's three slam champions were, at the times of their triumphs, just 21 (Sofia Kenin - Australian Open), 19 (Iga Swiatek - French Open) and 22 (Osaka - US Open).

The women's game has not seen anything comparable in terms of youthful winners of its blue riband tournaments since 2004, when the 21-year-old Justine Henin won in Australia, Anastasia Myskina landed the Roland Garros title at 22, Maria Sharapova was a 17-year-old bolter to Wimbledon glory and 19-year-old Svetlana Kuznetsova scored a stunning Flushing Meadows victory.

Last year does not touch the 1997 season, when a 16-year-old Martina Hingis won the Australian Open, Wimbledon and US Open, denied a grand slam clean sweep by 19-year-old Iva Majoli's shock French Open final win over the Swiss.

But women's tennis is still seeing a remarkable shift to relative youth.

The 2019 season saw a then 19-year-old Bianca Andreescu scoop a stunning US Open win, while Ash Barty took the French Open.

Andreescu has been sidelined with a knee injury since the 2019 WTA Finals, but she is back for Australia, where Queenslander Barty, now 24, is the home hero.

Brace for the prospect of Andreescu and Barty joining Kenin, Swiatek and Osaka in a group of five who can take the women's game boldly into the post-Williams era.

But the Williams era isn't over

This is true, and again Serena will make another attempt to land that elusive 24th grand slam, the one that would move her level with Margaret Court on the all-time list.

She remains, at the age of 39, a magnificent competitor and a beguiling player, as does sister Venus, who turns 41 in June.

Serena has lost her last four grand slam finals, however, and the most recent run to a title match came almost 18 months ago in New York, where Andreescu had her number.

As the new gang of five threaten to pull away from the old establishment, perhaps Williams is now in the next group, along with the likes of Simona Halep, Victoria Azarenka and Petra Kvitova: still perfectly capable of winning another slam or even multiple slams, but it feels important to strike now.

Serena has not won any of her last 10 slams, making it the longest span in her professional career without winning a major.

Barty party, or Sofia the second?

Osaka begins the Australian Open as favourite with bookmakers, but world number one Barty will have home support and could make that count. How she performs will be keenly watched, given she chose not to travel once the COVID-19 pandemic hit last year, sitting out 11 months.

Should Barty get on a roll, hopes will be high she can become the first Australian woman to take the title since Chris O'Neil in 1978. Last year, Barty fell in the semi-finals to Kenin, and she will be eager to land a second slam title.

Kenin, whose intense concentration and steely resolve helped her pull off last year's shock Melbourne win, and follow up with a run to the French Open final, can be a match for anyone. She will be aiming to become the first woman to win back-to-back Australian Open titles since Azarenka in 2012 and 2013.

Success on this level has come perhaps ahead of schedule for the American, and the same can be said for Swiatek, whose demolition of the field at Roland Garros in October made a mockery of her being ranked number 53 in the world.

The teenage Polish player became her country's first grand slam singles champion, and with that status comes the expectation she will follow it up. How that turns out for her will be one of the most intriguing of sub-plots in the new season.

Changing priorities

Halep said in a recent WTA interview that winning an Olympic medal was her "main goal" for 2021, although Osaka will also have the Tokyo Games firmly circled in her diary.

For the likes of those other players among the 16 slam winners in the Melbourne draw, there will be differing targets this year, too.

Angelique Kerber, Sloane Stephens, Jelena Ostapenko and particularly Garbine Muguruza may yet come good again on the big stage at some point this season.

For Venus Williams, Kuznetsova and Samantha Stosur, it may be a case of one final hurrah.

As the likes of Coco Gauff emerge as potential future big-stage winners, and fledgling ambassadors, the women's game looks in safe hands.

Serena Williams roared into the quarter-finals of the Yarra Valley Classic with a 6-1 6-4 victory over Tsvetana Pironkova on a star-studded day of action in Australia.

The 23-time grand slam champion was in fine form at Melbourne Park, where the biggest names in women's tennis were competing across multiple tournaments, as she sealed a straight-sets triumph to continue her preparations for a shot at an eighth Australian Open title.

In doing so the 39-year-old extended her head-to-head record over the Bulgarian to 6-0 and was delighted to get the job done.

"It's definitely nice to get another win," the American said during her on-court interview.

"She's clearly a great player, so it wasn't easy, but it was good to come through."

Speaking at her media conference, Williams added: "Last time it was an incredible three-set match, so today I was like, 'All right, let's really try and focus and learn to do better than last time.'"

World number one Ash Barty had a less straightforward path to the last eight, requiring three sets to see off Marie Bouzkova.

The home hope ultimately prevailed 6-0 4-6 6-3, with second seed and reigning Australian Open champion Sofia Kenin also taken the distance in a 5-7 7-5 6-2 win over Jessica Pegula, as Nadia Podoroska dug deep to down Petra Kvitova 5-7 6-1 7-6 (9-7).

With Barty now set to face Shelby Rogers, Danielle Collins awaits Williams having impressively defeated third seed Karolina Pliskova 7-6 (7-5) 7-6 (7-3), while Garbine Muguruza overcame Anastasia Pavlyuchenkova 6-1 6-2 to set up a meeting with Kenin.

In the Gippsland Trophy, the top three seeds all dodged upsets, with two-time grand slam winner Simona Halep, 2019 Australian Open victor Naomi Osaka and 2018 Tour Finals champion Elina Svitolina safely navigating through the last 16.

Fifth-seeded Briton Johanna Konta failed to convert two match points as she succumbed to a 4-6 7-6 (12-10) 7-6 (7-4) defeat to Irina-Camelia Begu.

Meanwhile, at the Grampians Trophy there were wins for Anett Kontaveit, Jennifer Brady and Angelique Kerber.

World number one Ash Barty won her first WTA Tour match in almost a year at the Yarra Valley Classic, while Naomi Osaka got her Gippsland Trophy campaign going with a victory.

Barty sat out the vast majority of the 2020 season due to the coronavirus pandemic but marked her comeback with a 6-3 6-3 success over Ana Bogdan at Melbourne Park.

The Australian will face Marie Bouzkova next after the Czech defeated Aliona Bolsova on Tuesday.

Garbine Muguruza raced past Alison Van Uytvanck 6-2 6-0 and she was joined in the third round by Petra Kvitova, who battled to beat Venus Williams 7-6 (8-6) 7-5.

Reigning Australian Open champion Sofia Kenin, who was 7-5 up when Camila Giorgi retired from their match, is also through.

In her first match since winning the US Open in September, Osaka cruised to a 6-2 6-2 success against Alize Cornet and will meet Katie Boulter after the Briton came from a set down to beat Coco Gauff 3-6 7-5 6-2.

Iga Swiatek was also making her first appearance since winning a major title – the French Open last October – and after a slow start won 10 of the final 11 games to beat Kaja Juvan 2-6 6-2 6-1.

Aryna Sabalenka ended 2020 with back-to-back titles in Ostrava and Linz, before kicking off the new year with another trophy in Abu Dhabi. However, her run of 15 straight victories ended with a 1-6 6-2 1-6 loss to Kaia Kanepi.

Bianca Andreescu was due to gear up for the Australian Open by contesting the Grampians Trophy this week but withdrew from the competition to focus on training instead.