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). It's the first time Djokovic has ever retired in a major.

An injured Novak Djokovic has quit after dropping the first set of his Australian Open semifinal against Alexander Zverev.

Novak Djokovic was booed by a section of the crowd at the Rod Laver Arena in Melbourne after he retired mid-match due to injury during the semi-final encounter against Alexander Zverev.