No man has dominated the Australian Open like Novak Djokovic, but the steely Serb's reign over the hard courts of Melbourne Park may be set for its biggest challenge in years when the tournament gets under way tomorrow.
Bidding for a record-extending ninth Australian Open title, the world No 1 and double-defending champion remains the runaway favourite at his favourite grand slam where he once remarked that he felt touched by the "divine".
Yet, for once, Djokovic may hear the rumbling of hooves as the likes of Austrian Dominic Thiem and Germany's Alexander Zverev look to storm the fortress.
Djokovic won his eighth Australian Open title last year and finished the Covid-19 pandemic-blighted 2020 season with the top ranking for a sixth year.
Record reign
But it was a tumultuous season for the 33-year-old as he suffered a slew of setbacks on and off the court.
Disqualified from the US Open for accidentally hitting a ball into a line judge, Djokovic was thrashed by Rafa Nadal in the French Open final and bundled out of the ATP Finals in the last four by Thiem.
He now heads into the Australian Open with his cloak of invincibility frayed and with younger rivals smelling blood.
With Roger Federer absent after knee surgery, victory would ensure Djokovic banks enough points to eclipse the Swiss master's record reign of 310 weeks at world No 1.
An 18th grand slam title, meanwhile, would bring him within two of Federer and Nadal's shared record of 20.
Barring a first-round shock in 2016, Nadal has reached the Australian Open quarterfinals every time he has appeared since 2000, but the Spaniard has been unable to add to his sole 2009 championship.
Victory would secure the outright grand slam record of 21 titles, but a sore back has clouded his preparations, and he has not beaten Djokovic on a hardcourt in seven years.
Federer's absence and Nadal's struggles have only fuelled impressions that the old guard are on borrowed time.
The next generation, however, feel their time has come.
Yet the grand slam club is no longer just a "Big Three" affair, with Thiem having muscled in at the US Open last year.
Osaka has consistency
In the women's section, most of the attention will focus on hometown favourite and top seed Ash Barty, Simona Halep, Naomi Osaka, Bianca Andreescu and Iga Swiatek.
US Open champion Osaka has won three of the last five hardcourt grand slams and has been showing the sort of power and consistency that could make her the next dominant force in women's tennis.
The 23-year-old is seeded third but the rankings are perhaps not as reliable a gauge as they might be in other years because of the disruption to the international tennis circuit caused by the Covid-19 pandemic.
While Osaka played only four tournaments last season, Barty holds the top ranking despite playing her first competitive matches in almost a year in the Australian Open warm-ups last week.
The 2019 French Open champion reached the semifinals at her home grand slam last year - a career best - and will certainly not lack support from the restricted crowds as she bids to give Australia a first singles champion since Chris O'Neil in 1978.
Barty has looked fit and resilient in her warm-up matches and enjoyed what looked like a straightforward path to the business end of the tournament in Friday's draw, which paired her with world No 77 Danka Kovinic in the opening round.
American Sofia Kenin would have to rank as the grand slam form player after winning her first major at last year's Australian Open and reaching the final of the delayed French Open.
The 22-year-old fourth seed can be frustratingly inconsistent but should have more than enough quality to get past her first-round opponent, local wildcard Maddison Inglis, and into the second week.
Andreescu has been sidelined by a succession of injuries since soon after she won the 2019 US Open and many feared the worst when she pulled out of the Grampians Trophy warm-up last week.
The Canadian reassured her fans this week that the move was purely precautionary, however, and that she would be on court to face lucky loser Mihaela Buzarnescu in the first round.
Swiatek, who might struggle to match her fairytale run to the French Open title last year in only her third outing in the main draw at Melbourne Park, has been drawn in the same quarter as Halep and Serena Williams.
It was the humiliating fourth-round loss to the Polish teenager at Roland Garros that put paid to Halep's hopes of taking the No 1 ranking off Barty - and gave a reminder of the 29-year-old Romanian's sometimes fragile temperament.
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