Novak Djokovic's father says the world No 1 is unlikely to play at the Australian Open early next year unless rules on Covid-19 vaccinations are relaxed.
Organisers of the year's first Grand Slam - which starts on January 17 - have said that all players will have to be vaccinated in order to take part.
Djokovic has so far declined to disclose whether he is vaccinated and his father told Serbia's TV Prva that governing body Tennis Australia's stance on players being vaccinated was tantamount to 'blackmail'.
According to news website, B92, Srdjan Djokovic said: "As far as vaccines and non-vaccines are concerned, it is the personal right of each of us whether we will be vaccinated or not.
"No one has the right to enter into our intimacy.
"Under these blackmails and conditions, (Djokovic) probably won't (play).
"I wouldn't do that. And he's my son, so you decide for yourself."
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Djokovic has been dominant in Melbourne, winning the tournament on nine occasions, including this year - when he came within a US Open final defeat of completing the calendar Grand Slam.
He sits on 20 men's Grand Slam titles, level with Roger Federer and Rafael Nadal for the most in history.
Nadal has confirmed he will play at Melbourne Park in January but Federer will miss the tournament as he recovers from another knee surgery.
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