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

Novak Djokovic retired injured after losing the first set 7-6(5) against Alex Zverev on Friday to put the German through to his first Australian Open final.

Djokovic, who retired due to injury after the first set, was booed by the crowd as he walked off Rod Laver Arena.

Defending champion Jannik Sinner continued his sizzling Australian Open run with a victory over American Ben Shelton.

The win sets up a showdown with Alexander Zverev of Germany in Sunday’s final. Earlier Friday, Zverev won the first set of his semifinal when Novak Djokovic missed a putaway volley in a tiebreak. Djokovic retired on the spot, unable to overcome the muscle tear he suffered in his quarterfinal win over Carlos Alcaraz Tuesday night.

Defending champion Jannik Sinner continued his sizzling Australian Open run with a 7-6(2) 6-2 6-2 win over American 21st seed Ben Shelton to reach a second straight final at Melbourne Park and book a meeting with Alexander Zverev.

The Madison Keys who will play two-time defending champion Aryna Sabalenka for the title at the Australian Open on Saturday night is not the same Madison Keys who was the runner-up at the U.S.

Aryna Sabalenka moved one win away from becoming the first woman since 1999 to win three consecutive Australian Open titles, recovering from a slow start to beat good friend Paula Badosa 6-4, 6-2 and return to the final.