Tennis star Novak Djokovic had a vaccine exemption to enter Australia after a Covid infection on 16 December, his lawyers say in court documents.
Djokovic was denied entry to Australia after landing in Melbourne this week to play in the Australian Open.
The world's top ranked tennis player is currently in an immigration detention centre ahead of a court case on Monday.
His case has caused a huge outcry in Australia and made headlines around the world.
Djokovic, 34, who has said he is opposed to vaccination, had been granted a medical exemption to play in the tournament in a decision that infuriated many ordinary Australians.