The player was due to play in the Australian Open after being exempted from vaccination rules.
World number one tennis player Novak Djokovic has been denied entry to Australia over an issue with his visa.
The player arrived in Melbourne on Wednesday where authorities noticed a mistake on his application.
Djokovic was due to play in the Australian Open, after being exempted from vaccination rules.
He has been told he will be deported but his lawyers have said they will challenge the decision, Australian media report.
The tennis star had been quizzed in a room at Melbourne airport for hours while his visa and exemption status was being investigated.
His team had not requested a visa that permits medical exemptions for being unvaccinated.
It is not clear whether he will remain in Australia while his lawyers attempt to overturn the decision.
Djokovic has not spoken about his vaccination status, but last year he said he was “opposed to vaccination”.
His treatment has provoked outrage in his native Serbia. Djokovic’s father, Srdjan Djokovic said his son was had been in a room guarded by police.
President Aleksander Vucic said the star was a victim of “harassment”, and that “the whole of Serbia”, supported him.
Earlier, Australia’s Prime Minister Scott Morrison said Djokovic would be refused entry to the country unless he provided evidence that he could not be vaccinated for medical reasons.
Australia is seeing tens of thousands of Covid-19 cases for the first time after enduring some of the world’s strictest restrictions.
The Australian Open begins on 17 January in Melbourne.