Nine-time Melbourne champion Novak Djokovic returns after being banned from last year’s Australian Open while Rafael Nadal is the men’s singles defending champion.
World No 1 Carlos Alcaraz is out injured however and the great Roger Federer is another missing following his retirement.
Meanwhile, world No 1 Iga Swiatek is the favourite to win an Australian Open women’s singles draw shorn of some of its biggest recent stars.
Ashleigh Barty, who lifted the trophy 12 months ago, and Serena Williams have retired, while the 2019 and 2021 winner Naomi Osaka is pregnant and absent.
Here’s a look at five men and five women to watch out for when the first Grand Slam of the year begins on Monday:
Novak Djokovic
The Serb is back at Melbourne Park for the first time since winning his ninth title in 2021 and says he “likes his chances”. He was kicked out of the country ahead of the tournament last year over his Covid vaccination stance.
The 21-time Grand Slam winner also missed the US Open for the same reason, but won Wimbledon and is heavy favourite at his most successful major despite a niggling hamstring injury.
Now 35, the former world number one finished a troubled 2022 with a record-equalling sixth ATP Tour Finals crown and began the new year in irrepressible form, winning his 92nd career title at the Adelaide International.
“I know when I’m healthy and playing my best, on this court (Rod Laver Arena) I have chances really against anybody,” he said.
Rafael Nadal
The 36-year-old Spaniard made the most of Djokovic’s absence to win the title in 2022, outlasting Daniil Medvedev over five sets in a more than five-hour thriller.
He made history in the process – the first man to achieve 21 Grand Slam singles crowns, making it 22 when he won a 14th French Open title.
But injuries hampered his season and he withdrew from Wimbledon after winning his quarter-final and exited in the last 16 at the US Open.
Now a father, Nadal struggled to find his best form at the ATP Finals in November and lost both of his matches at the recent United Cup, to Cameron Norrie and Alex de Minaur.
He is top seed in the absence of Alcaraz and insisted “my personal momentum is not bad, I tell you. I am good and happy.”
Daniil Medvedev
The 26-year-old Russian was unable to match his run to the Melbourne final at the French or US Opens last year and never had a chance at Wimbledon after being banned due to the Ukraine war.
He did win two titles and spent 16 weeks as world number one.
But it was an underwhelming year in the eyes of the 2021 US Open champion, who has slipped to eight in the rankings.
He began 2023 at the Adelaide International, where he was beaten by Djokovic in the semi-finals.
“Every time I play them (Djokovic and Rafael Nadal), before the match the only thought is I have to win,” he said.
Stefanos Tsitsipas
The world number four burst onto the scene at the Australian Open in 2019 when as a 20-year-old he dethroned defending champion Federer in the last 16.
He went on to reach the semi-finals that year and again in 2021 and 2022, highlighting the consistency that has made him a mainstay of the world’s top 10 for nearly four years.
The Greek star won the ATP Masters 1000 title in Monte Carlo last year along with another on the grass of Mallorca.
But a Grand Slam crown remains elusive with his runner-up showing at Roland Garros in 2021 his best result at a major.
He began the new season on the Greek team at the United Cup, winning all four matches including the scalps of Matteo Berrettini and Grigor Dimitrov.
Nick Kyrgios
Love him or hate him, Kyrgios is a showman and nowhere more so than on home turf in Melbourne, drawing huge and rowdy crowds.
While his frequent tantrums have long overshadowed his talent, the enigmatic Australian had a stellar 2022, making a barnstorming run to a first Grand Slam singles final at Wimbledon, losing to Djokovic.
He has never gone past the Australian Open quarter-finals and his build-up has been hampered by an ankle injury, but the unpredictable Kyrgios is an outside chance if he can handle the pressure and keep his cool.
Iga Swiatek
The 21-year-old seized her opportunity after the retirement of Barty to dominate 2022, securing eight WTA titles and becoming the first woman in six years to win two Grand Slams in the same season – at Roland Garros and New York.
After losing the Australian Open semi-final to Danielle Collins, Poland’s Swiatek did not look back, embarking on an incredible 37-match winning streak.
She begins her campaign on Monday against Jule Neimeier, the German world number 68, who reached the quarter-finals at Wimbledon last year and took a set off Swiatek in the last 16 at Flushing Meadows.
“We played in the US Open, and you saw how intense that match was, how tough,” Swiatek said. “It’s not going to be easy.
Ons Jabeur
The Tunisian world number two appears to be on the cusp of a Grand Slam breakthrough, having been runner-up at Wimbledon and the US Open last year.
The 28-year-old has set herself a 2023 target of toppling Swiatek from the number one ranking and becoming the first Arab and African woman to win a Slam.
Late bloomer Jabeur was 26 when she lifted her maiden WTA title in 2021 at Birmingham, adding Madrid and Berlin trophies last year.
“I will try to use that experience from last year because it was kind of tough,” Jabeur said ahead of her first-round clash against Slovenia’s Tamara Zidansek on Tuesday.
“My goal is to not lose any more finals, but just use that to be ready for the next one.”
Jessica Pegula
The 28-year-old world number three comes into Melbourne Park after starring for the victorious USA team at the United Cup, where she won four of her five matches and beat Swiatek.
Pegula, whose parents are the billionaire owners of the Buffalo Bills NFL franchise, reached the Australian Open quarter-finals in 2021 and last year, where she was outclassed by a rampant Barty.
With Barty out of the way she could prove the biggest challenge to Swiatek.
The easy-going Pegula, who faces Romania’s world number 143 Jaqueline Cristian on Monday, admitted last year to spending time relaxing at the blackjack table in a Melbourne casino.
Aryna Sabalenka
The explosive Belarusian promised she would be up for a “big fight” at the Australian Open after winning in Adelaide this month for the 11th WTA title of her career.
The 24-year-old left-hander sprung back into form last season, reaching the semi-final at the US Open and the WTA Tour finals championship match, where she lost to Caroline Garcia.
Sabalenka can suffer hugely from nerves, which were all too obvious at her two season-opening tournaments in Australia last year when she was reduced to tears as her serve collapsed.
Seeded five, she will begin her campaign against 73rd-ranked Tereza Martincova of the Czech Republic on Tuesday.
Coco Gauff
The 18-year-old goes into Melbourne Park on a high after winning her third WTA title at the Auckland Classic this month and warned Saturday that her “best is yet to come”.
The seventh seed first won hearts as a 15-year-old in 2019 at Wimbledon when she arrived as a qualifier and reached the last 16, beating five-time champion Venus Williams along the way.
Her exploits sparked “Coco Mania” and she went on to win her first WTA title that year with her second coming in 2021, a year in which she beat Barty in Rome.
Last year she reached her first Grand Slam final, losing to Swiatek at Roland Garros.
The American has the honour of playing in Monday’s opening match on the showpiece Rod Laver Arena against the Czech Republic’s world number 48 Katerina Siniakova.
Gauff would be the youngest Australian Open champion since a 16-year-old Martina Hingis in 1997 if she lifts the winner’s Daphne Akhurst Cup.