Men's top-ranked tennis player Novak Djokovic says after visa reinstatement that he remains focused on Australian Open

Djokovic's mother alleges he's suffered 'torture' in Australia (0:47)

Dijana Djokovic opens up about her son's experiences after a court ruled he should be released from hotel quarantine. (0:47)

MELBOURNE, Australia -- The world's top-ranked men's tennis player, Novak Djokovic, expressed gratitude that an Australian judge overturned his visa cancellation on Monday.

Djokovic tweeted a photo of himself standing on a tennis court at Rod Laver Arena in Melbourne saying, in part, "Despite all that has happened, I want to stay and try to compete @AustralianOpen I remain focused on that. I flew here to play at one of the most important events we have in front of the amazing fans."

He also thanked his supporters for encouraging him throughout his ordeal, which began when he arrived in Melbourne on Wednesday as government authorities canceled his visa after deciding he didn't meet the criteria for an exemption to an entry requirement that all non-citizens be fully vaccinated.

Court documents state that the 34-year-old tennis star is not vaccinated.

But he appealed the cancellation at the virtual court hearing on Monday, arguing he did not need proof of vaccination because he had evidence that he had been infected with the coronavirus last month.

Australian medical authorities have ruled that a temporary exemption for the vaccination rule can be provided to people who have been infected with COVID-19 within six months.

Federal Circuit Court Judge Anthony Kelly noted that Djokovic had provided officials at Melbourne's airport with a medical exemption given to him by Tennis Australia and two medical panels.

"The point I'm somewhat agitated about is, what more could this man have done?'' Kelly asked before reinstating Djokovic's visa and ordering him released from the Melbourne quarantine hotel, where he has been held since Thursday.

"I want to thank everyone in the world who who stood up and supported him in Melbourne in front of that so-called hotel," said Djokovic's mother, Dijana, at a news conference the family held in Belgrade. "This is his biggest win in his career, it is bigger than any Grand Slam.

"He has done nothing wrong, he hasn't broken any of their laws. He has been subject to harassment. He fought against the system and the government because he had the right to be there."

Djokovic's brother Djordje added, "Truth and justice have come out and I hereby want to thank Australia's legal system and judge Kelly, who has been unbiased and neutral as he took on board all the facts since he [Djokovic] landed at Melbourne airport, including the bullying he's been through."

Djokovic's ordeal is not yet over. Government lawyer Christopher Tran told the judge after the ruling that the minister for Immigration, Citizenship, Migrant Services and Multicultural Affairs, Alex Hawke, "will consider whether to exercise a personal power of cancellation.''

Hawke was still considering whether to cancel Djokovic's visa a second time, a spokesman said later on Monday.

That would mean that the nine-time Australian Open winner and defending champion could again face deportation and could miss the tournament, which starts on Jan. 17. It could also bar him from the country for three years.

Djokovic has 20 Grand Slam singles titles, a men's record he shares with Roger Federer and Rafael Nadal.

The Associated Press and Reuters contributed to this report.