MELBOURNE: World tennis No. 1 Novak Djokovic was back in practice hours after winning a court challenge to remain in Australia on Monday, thanking the judge who released him from immigration detention and saying he remained focused on his bid for a record 21st Grand Slam win in Melbourne. The fight over his medical exemption may not be over, however, as the Australian government said it was still considering another move to deport him. “I am pleased and grateful that the judge overturned my visa cancellation,” Djokovic wrote on Twitter where he posted a photograph of himself on court at the Rod Laver Arena at Melbourne Park. “Despite all that has happened I want to stay and try to compete at the Australian Open.” Earlier Judge Anthony Kelly had ruled the federal government’s decision last week to revoke the Serbian tennis star’s visa amid was “unreasonable” and ordered his release. “Novak is free and just a moment ago he went to the tennis court to practice,” Djokovic’s younger brother Djordje told a family news conference in Belgrade. “He’s out there to set another record.” Djokovic, who arrived in Australia last week to defend his Australian Open title, had spent the day at his lawyers’ chambers. There were chaotic scenes on Monday evening as supporters who had gathered outside the lawyers’ office chanting “Free Novak!” surged around a black car with tinted windows leaving the building, while police at one stage used pepper spray as they tried to clear a path. A spokesman for Immigration Minister Alex Hawke said he was considering using his broad discretionary powers he is given by Australia’s Migration Act to again revoke Djokovic’s visa. Such a move could include a three-year ban on re-entering Australia. “The minister is currently considering the matter and the process remains ongoing,” the spokesman said. The controversy has been closely followed around the world, creating diplomatic tensions between Belgrade and Canberra and sparking heated debate over national vaccination rules. The Australian Open begins on Jan. 17. Djokovic has won the tournament, one of tennis’s four Grand Slams, for the last three years and nine times overall. Spanish rival Rafa Nadal called the drama surrounding the buildup to the tournament a “circus.” “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,” Nadal told Spanish radio Onda Cero. The authorities’ efforts to let the media and public follow events in court at times descended into farce, with pranksters hijacking internet links to stream loud music and porn. Judge Kelly said he had quashed the decision to block Djokovic’s entry to Australia because the player was not given enough time to speak to tennis organiZers and lawyers to respond fully after he was notified of the intent to cancel his visa. Officials at Melbourne’s airport, where Djokovic had been detained on arrival late on Wednesday, reneged on an agreement to give Djokovic until 8.30 a.m. to speak to tournament organiser Tennis Australia and lawyers, Kelly said.