By Ian Ransom

MELBOURNE (Reuters) - Melbourne's notoriously changeable weather threatened to wash out the soft launch of the Australian Open on Monday but the rain was unable to dampen the cheer among tournament organizers enthused by Nick Kyrgios's weekend victory in Japan.

The tempestuous 21-year-old, Australia's brightest hope of a men's grand slam champion since twice winner Lleyton Hewitt, clinched the Japan Open on Sunday with an impressive win over rising Belgian David Goffin.

For a player who professes no love for tennis and has admitted to being "a little bit soft", Kyrgios has won all three of his titles this season, his latest in Tokyo the biggest of a still fledgling career.

Kyrgios clobbered 25 aces past Goffin but a more telling statistic might have been the zero tantrums committed by the hot-headed Australian during the tense three-setter.

The prospect of a fit, in-form and happy Kyrgios making a deep run at the Australian Open would be a dream outcome for the tournament's organizers but not one they were willing to indulge out loud on Monday, lest the wish not come true.

"It's a long journey; it's a long-term journey when it comes to Nick," a wary Tennis Australia CEO Craig Tiley said after being soaked by a spring shower at the tournament's launch near Melbourne Park.

"But he's certainly, we've felt, more recently turned the corner.

"But his performances this past week has been tremendous in winning his third professional title.

"And that's fairly remarkable. There's a lot of pressure on him. We do what we can. We have a long-term view of it."

Easing the pressure on Kyrgios has almost become a mantra in Australia, where a litany of former players, coaches and pundits have previously offered a mixture of well-intentioned advice and blunt criticism.

Most, if not all of the feedback, has been summarily dismissed and its purveyors ridiculed on Kyrgios's social media accounts.

But where other would-be mentors have failed, Hewitt, Australia's Davis Cup captain, has proved the most successful in coaxing the prickly young talent back into the national fold.

The 35-year-old's unwavering defense of Kyrgios, warts and all, was rewarded when the player pledged himself for Davis Cup duty and helped Australia retain its place in the World Group with a playoff win over Slovakia last month.

"He's definitely been better, no doubt," said Hewitt when asked whether Kyrgios had become mature.

"He was fantastic at the Davis Cup tie in Sydney.

"He's made Davis Cup a massive priority going in to next year ... and he is ready to stand up and be the leader of our Davis Cup team."

(Editing by Greg Stutchbury)