In the early hours of Thursday morning, World No1 and defending Australian champion Novak Djokovic was denied entry into Australia after his visa was cancelled by border force officials at Melbourne airport. Djokovic was granted a controversial exemption to enter Australia and compete in the Australian Open, but was held up at Melbourne airport by authorities for several hours before his visa was cancelled. Djokovic, who has publicly criticised mandatory vaccines, has refused to disclose his inoculation status and said he had been granted a medical exemption to compete in Australia.