MELBOURNE (REUTERS) - Rafael Nadal called Novak Djokovic's Covid-19 vaccination controversy in Australia "a circus" and joked that he would prefer that the world No. 1 tennis player didn't play at the Jan 17-30 Australian Open.

Djokovic was released from Australian immigration detention on Monday (Jan 10) after winning a court challenge to remain in the country to pursue his bid for a record 21st Grand Slam title at the Australian Open.

"Whether or not I agree with Djokovic on some things, justice has spoken and has said that he has the right to participate in the Australian Open and I think it is the fairest decision to do so, if it has been resolved that way. I wish him the best of luck," Nadal, who is also chasing a record 21st Major, told Spanish radio Onda Cero on Monday.

After being denied entry into Australia for arriving without being vaccinated against Covid-19, Djokovic was detained by officials at the border on Thursday (Jan 6) amid a storm of protest about the decision to grant him a medical exemption from vaccination requirements to play in the Australian Open.

"On a personal level, I'd much rather he didn't play," Nadal said, laughing along with interviewer.

"It's sports, many interests move around it, on a general level, at an economic, advertising level. Everything is much better when the best can be playing," Nadal said, before once again defending vaccination.

"The most important institutions in the world say that the vaccine is the way to stop this pandemic and the disaster that we have been living for the last 20 months."

During a hearing on Monday, Judge Anthony Kelly ruled that the federal government's decision last week to revoke Djokovic's visa was "unreasonable" and ordered the 34-year-old to be released.

News of the ruling was greeted with noisy celebrations of drum beating and dancing by a group of around 50 supporters, many draped in the Serbian flag, outside the Melbourne court.

Lawyers for the federal government, however, indicated the fight may not be over, telling the court Immigration Minister Alex Hawke was reserving the right to exercise his personal power to again revoke Djokovic's visa.

After confirming that such a step, if taken, would bar the Serb from Australia for three years, Kelly warned the government lawyers that "the stakes have now risen, rather than receded."

Hawke's office did not immediately respond to requests for comment.