An email from Tennis Australia, offering television networks footage of defending champion Naomi Osaka’s arrival in Melbourne, arrived midway through Tuesday. Even for a country renowned for celebrating the arrival of any international celebrity with a chorus of publicity, the sight of the Japanese superstar on the tarmac was a welcome relief. The recent Covid-19 spike has added insult and uncertainty to the injuries that have already ruled legends Serena Williams and Roger Federer out of the Australian Open. If this year’s grand slam was unprecedented, next month’s edition is shaping as another tournament of great apprehension given the pandemic is heating up yet again. Former finalist and US Open champion Dominic Thiem withdrew Wednesday with a wrist problem. Three of this year’s women’s semi-finalists, led by Williams, are out injured. Karolína Plíšková, who played a ripper of a Wimbledon final against Ash Barty, will miss, as will former US Open finalist Kei Nishikori, the high-profile compatriot of Osaka. Rafael Nadal is in Spain recovering from a Covid-19 infection contracted at an exhibition in Abu Dhabi last week that has now seen five positives among a small group of players, including Russian contender Andrey Rublev. It is not yet clear whether Nadal, the 2009 Australian Open champion, will be at Melbourne Park, but local officials are quietly confident the 20-time major winner will travel. Five-time Australian Open finalist Andy Murray, who attended the UAE exhibition, arrived on Wednesday after receiving a wildcard into next month’s grand slam. As for Novak Djokovic, the undisputed king of Melbourne Park, there is no certainty at all regarding his presence at the Australian Open. Late on Wednesday he pulled out of the ATP Cup, due to begin in Sydney on New Year’s Day. For every breathless report about the Serbian, there is no clarity as to whether the nine-time Australian Open champion is vaccinated or not. Little wonder then at the excitement and relief surrounding the arrival of the four-time major champion Osaka, whose return after a mental health break provides a boost of star power. Tournament organisers pulled off tennis’s version of a miracle in February, with players chartered into the country and quarantined before being unleashed on the courts of Melbourne Park. Successfully negotiating the threat posed by the Omicron variant for the summer of 2022 is providing challenges that are no less complex and stressful. While questions abound about the participation of some big names, there is ample evidence to state those who actually get to the baseline possess more than enough punch to ensure another quality edition of the Happy Slam. The US Open proved a clear illustration, with the success of Emma Raducanu, and her final against Leylah Fernandez, prompting stunning television ratings in America and abroad. Daniil Medvedev, the US Open champion and a finalist in Melbourne in February, is clearly a leading title threat after dismantling Djokovic in New York. Alexander Zverev peaked at the ATP Finals when defeating Medvedev and seems certain to break his duck at a major sooner rather than later. The interest and expectation surrounding Barty in her bid to break an Australian Open drought by locals dating back to the success of Chris O’Neil in 1978 is enough to ensure a high-level of patriotic interest. The world No.1 practised on Rod Laver Arena with Billie Jean King Cup teammate Sam Stosur on Wednesday and will head to Adelaide for a tournament next week. She carries star billing for a WTA Tour event in Sydney in the week prior to the year’s first major. Clips of players practising against mattresses laid up against the wall of their hotel rooms heralded an unusual and enormously expensive Australia Open in 2021. The conditions will be less onerous this year, with an extended stint in quarantine reserved solely for those who test positive. But it is certain some will be hindered. The threat posed by Omicron has the potential to wreak havoc on draws over the next month in Sydney, Adelaide and Melbourne. Already Canadian star Denis Shapovalov is serving a 10-day stint in Sydney. Frenchman Benoit Paire announced he is positive again on Wednesday. Others are certain to follow suit. Officials are trying to minimise risk. So, too, star players. Some will stay in homes, with an agent of a leading player telling Guardian Australia that contact with the star will be restricted to a small handful of people over the next month. The majority of players will stay in what Tennis Australia has dubbed a “minimised risk environment” at Crown Hotels, though they will be free to move about Melbourne. Unlike last February, entire plane loads of players will not have to serve strict quarantine should a person aboard a flight to Australia test positive. But it was somewhat surprising to see photos of players on a flight from South America mixing freely and mask-free over a card game given what is at stake. The majority of the 17 flights bringing stars to Australia have now arrived. Another few are scheduled to arrive from late next week for those who are not playing in the events on offer in suburban and regional Australia. For all the optimism, perhaps the only sure thing about the month ahead is the lack of certainty.