Novak Djokovic has taken to social media to hit back at John McEnroe and other critics who questioned the severity of his injury at the Australian Open

Martina Navratilova unloaded on the Australian Open crowd, slamming their treatment of Novak Djokovic as "disgusting." Moments after retiring injured from his semifinal match against Alexander Zverev at Melbourne,

Novak Djokovic is out of the Australian Open in stunning fashion. The 24-time slam champion medically retired immediately after dropping the first set of his semifinal match against No. 2 Alexander Zverev in a tiebreak 7-6 (5).