Thousands of tennis fans haven’t let Melbourne’s cold and wet weather keep them away from the Australian Open.

Melbourne’s dreary summer weather has done little to dampen the spirits of tennis fans, with thousands pouring through the gates as the 2018 Australian Open gets underway.

Light showers fell on Melbourne Park about half an hour before the start of play on Monday morning but people still lined up in droves to enter the grand slam site.

American comedian Will Ferrell jetted into Melbourne to catch the first day of the tennis, and is expected to watch No. 1 Rafael Nadal take on the Dominican Republic’s Estrella Burgos and Australia’s home hope Daria Gavrilova against American qualifier Irina Falconi.

Olympic champion swimmer Michael Klim, Australian cricketer Aaron Finch and tennis legends Neale Fraser and Frank Sedgman will also be courtside.

Last year’s memorable men’s final between Roger Federer and Rafael Nadal helped boost total crowd attendance for whole tournament to 728,763, a record since the tournament’s inception in 1905.

Australian Open boss Craig Tiley declared anything’s possible as the Melbourne Park major gets under way.

A year after clashing in the most anticipated Open final ever, ageless tennis titans Roger Federer and Rafael Nadal are seeded to square off once again for the title, after in 2017 completing the most extraordinary seasons of their decorated careers.

Languishing in the rankings after injury-enforced absences, Federer and Nadal rolled back the years to set up what many believed was one last dance on the big stage.

But after sweeping to all four slams in a wildly retro 2017, the living legends are back in Australia as the world’s top two players and favoured to extend their compelling grand slam rivalry to a 14th year.

With five-time finalist Andy Murray recovering from hip surgery in Melbourne and six-time champion Novak Djokovic and Stan Wawrinka – the only other man to claim the Norman Brookes Challenge Cup in the past decade – also under fitness clouds, Federer and Nadal are the only men under single-figure odds with the bookmakers.

Their biggest threats look to be young gun Alexander Zverev, local hope Nick Kyrgios and world No.3 Grigor Dimitrov.

“It’s going to be an interesting first few days of the event,” Tiley said.

“It’s going to be a big-time telling sign for how the rest of the event is going to go.

The world’s best will be playing for a record $55 million in prize money over the next fortnight.

Apart from Kyrgios, Australia has two big women’s hopes in 17th-seeded Sydney finalist Ashleigh Barty and 23rd seed Daria Gavrilova.

Kyrgios, up against Brazil’s world No.100 Rogerio Dutra Silva, and Gavrilova, playing a qualifier, are among nine Australians opening their campaigns on Monday.

French Open champion Jelena Ostapenko, playing her first match under the guidance of Australian coach David Taylor, has the honour of opening Rod Laver Arena proceedings against veteran Italian Francesca Schiavone.

Nadal, Dimitrov, Venus Williams, Caroline Wozniacki and Samantha Stosur are among the other stars in day one action.

– AAP