THE pyrotechnics stretched all the way from the tiny pacific island of Kiribati to the Sydney Harbour Bridge as the continent of Oceania kicked off 2015 and fireworks are also customary when the tennis year gets under way in earnest at Melbourne Park.

The Australian Open, the 105th running of which begins in the country's self-styled cultural capital tomorrow, is the most unpredictable of Grand Slam tournaments. Uncertainties of form, preparation, sweltering summer heat and the usual early-season injuries all tend to come into play, lending a random factor to this tournament akin to the rattling of a giant tennis tombola. The likes of Jimmy Connors, Stefan Edberg, Novak Djokovic as well as Stan Wawrinka 12 months ago, all recorded their first major win here, with Jo-Wilfried Tsonga and Marcos Baghdatis just two of the surprise finalists.

In some ways this sense of early-season anarchy seems even more acute this year. During 2014, the four major titles were scattered among four players, with Wawrinka and US Open winner Marin Cilic joining the list of Grand Slam victors for the first time. Throw in the emergence of Grigor Dimitrov, Milos Raonic and Kei Nishikori and some feel further disruption to the historic four-way stranglehold is inevitable. The Croat's sore shoulder and Tsonga's bad arm make them the most notable absentees in Melbourne, and rising home favourite Nick Kyrgios is nursing a back problem, but most of the medical question marks relate to the player from Mallorca who this fortnight will be bidding to become the first man in the Open era to win all four major titles twice.

Two years ago Rafa Nadal's decision to skip this tournament as he recovered from knee surgery paid dividends with one of the finer tennis seasons in recent memory, but this time the Spaniard, who had an appendectomy on November 3, will have to find his form and rhythm along the way.

"His game is rusty and he needs miles in his legs to feel his game and that is what he has been desperately trying to do," says Darren Cahill, the ESPN pundit who is one of the world's finest tennis analysts. "I watched him play a couple of practice sets here in Melbourne and he is struggling a bit with his game so he will be vulnerable in the early rounds."

It is a similar scenario to that facing Andy Murray 12 months ago, as he rehabbed from back surgery in late 2013, but this time the Scot's timing seems perfect. With a backdrop of some notable alterations to his coaching team - the departures of Dani Vallverdu and Jez Green but retention of Amelie Mauresmo - some fine-tuning of his practice arrangements, an engagement to Kim Sears, a change of kit supplier and the launch of a new logo, those who know Murray well feel he is in good fettle and expect him to thrive.

Cahill is one of them. He feels Murray may be playing as well as anyone in the world right now. The only problem is that he will have to be. The 27-year-old's lowly No 6 seeding means he may have to beat Dimitrov, the evergreen Roger Federer, Nadal and then world No 1 Novak Djokovic if he is to rack up his third major win on the court where he has suffered three final defeats.

"I got to see Andy in Perth playing all his matches at the Hopman Cup and I spoke to him at length," said Cahill. "He is very happy with the way he feels coming into the 2015 season. It looks like he has added some sprint work and some power work into his programme and he is feeling great on the court. He is playing very good tennis and, when you look at the stuff in his game that can normally get him into trouble against the best players, it looks like he is also becoming a bit more forthright in the way he is approaching most of his baseline rallies.

"The serve is a constant thing that he is working on, and hopefully we will see some improvement on that, particularly on the second serve. He has a new look to his team and that can only challenge him to find a way to get it done this year. The form we saw at the end of the year was great. You can take every loss and learn from it and that loss to Federer [6-0, 6-1 at the O2 Arena in London] I think he took in the right fashion.

"I am expecting a big year from him. I think he will get back into the mix and it would not surprise me if he won another major this year. He has got a bit to prove and he likes being the underdog, proving things to people who tell him he can't get it done. To be honest, he may be playing the best tennis of all the players right now. He has been pretty faultless so far."

If the Australian Open is a model of unpredictability, the one metronome of consistent excellence at this venue is Djokovic. The world No 1 has emerged strongest in three of the last four Australian Opens and, like Federer, is bidding to become only the second man in history, after Roy Emerson, to win five Australian titles. While he went down, surprisingly, to the giant Ivo Karlovic then skipped a meeting with Murray at an exhibition event in Abu Dhabi recently, the road to winning this title undoubtedly leads to beating him.

"It has been a remarkable love affair that Novak has had with the Australian Open," said Cahill. "His game suits the conditions down here incredibly well. He has managed to overcome obstacles with the heat to become one of the greatest athletes the game has seen. He doesn't have any weaknesses. We haven't seen a great deal of him but I don't think it matters.

"He finished the year incredibly well again and it is a little bit like the French Open with Rafa. He is the man to beat in my eyes, even if he did lose in the quarter-finals last year to Wawrinka in what was an incredible match. He is my pick to win. It will take an outstanding performance by anyone to beat him."