Australian Open: Authorities cancel Novak Djokovic's visa due to lack of evidence of medical exemption. The world number one, whose vaccination status is unknown, spent the night at Melbourne airport and has been asked to leave the country - FILE - Novak Djokovic (SRB) during his second round at the 2017 Australian Open at Melbourne Park in Melbourne, Australia, on January 19, 2017. Photo by Corinne Dubreuil/ABACAPRESS.COM

Serbia's Novak Djokovic uses a towel during a break in his men's singles final match against Austria's Dominic Thiem on day fourteen of the Australian Open tennis tournament in Melbourne on February 2, 2020.,Image: 496051070, License: Rights-managed, Restrictions: IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE, Model Release: no, Credit line: Profimedia