Gutted Novak Djokovic retires from Australian Open semifinal after just one set

The 24-time major champion was unable to continue after losing a gruelling opening set lasting an hour and 21 minutes on Rod Laver Arena.

The set went to a tiebreak after neither player broke serve, with Djokovic saving five break points and Zverev fending off three.

After the first 11 points of the tiebreak went with serve, Djokovic, who was serving at 5-6, netted a regulation forehand volley to hand Zverev the set.

Djokovic then immediately walked to shake hands with Zverev in a sad and shocking conclusion to what had promised to be a lengthy battle.

The 37-year-old Serbian entered the match having not practised since suffering the leg injury early in his epic four-set quarter-final win over Carlos Alcaraz on Tuesday.

Zverev, the World No 2, is through to his first Australian Open final and third Grand Slam championship match as he seeks his maiden major title.

To do so he will need to get past red-hot favourite World No 1 Jannik Sinner, who cruised into the final with a 7-6 (7-2) 6-2 6-2 victory over American Ben Shelton in just over two and a half hours.

In his post-match press conference, Djokovic explained the pain of his injury had become too much to fight through by the end of the set.

"I didn't hit a ball since [the] Alcaraz match, so until like an hour before today's match. I did everything I possibly can to basically manage the muscle tear that I had," the world No. 7 said.

"Medications and, I guess, the strap, and the physio work helped to some extent today. But yeah, towards the end of that first set I just started feeling more and more pain.

"It was too much, I guess, to handle for me at the moment. Unfortunate ending, but I tried.

"It's a muscle tear. Two years ago, I have managed it better. On the court it didn't bother me as much. This time that wasn't the case.

"So in these kind of instances I guess have you to try to do as much as you possibly can in the shortest amount of time, and that was the case.

"I had an extra day, so two days no match. So I thought it's going to be good enough maybe. But yeah, that wasn't the case, unfortunately."

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