Major concerns over Novak Djokovic's fitness ahead of Australian Open semifinal

The 24-time Grand Slam winner struggled with a leg injury during his last-eight victory over Carlos Alcaraz as he needed off-court treatment late in the first set.

He re-emerged from the change room with a heavily strapped left thigh, but managed to defeat Alcaraz in fourth sets to reach his 11th semi-final at Melbourne Park.

Djokovic admitted after the match that he was "concerned" about his injury.

"I will try to do as much as I possibly can with my recovery team, with my physio, today, tomorrow, the next few days. Probably skip training tomorrow. I'll see if I'm going to train in two days or not," he said.

"I'll take it day by day. Now it's really about recovery. I'm concerned. I am, to be honest, physically. But, if I manage somehow to be physically good enough, I think mentally, and emotionally, I'm as motivated as I can be.

"I'm just pleased with the way I was able to play throughout the entire tournament, including against one of the best players, one of the two or three best players in the word in the last three, four years. It's just a great win. I'm very proud of it."

After skipping training on Wednesday, Djokovic has now decided not to train on Thursday, meaning he will head into his match against Zverev without stepping onto the practice court after the Alcaraz match.

The semi-final is scheduled for 2:30pm Melbourne time (03:30GMT) on Thursday so he still has some time to recover.

The 37-year-old also admitted that the injury felt similar to the one he suffered in 2023 when he played with a hamstring tear.

On that occasion, he went on to lift his 10th Australian Open title and it was later revealed he had a three-centimetre hamstring tear.

"It's very similar to what I had few years ago. 2023, to be exact," he said. "I haven't done any tests obviously, [other than] with the physio when they took me off the court when I had the medical timeout. He strapped me, and then the doctor gave me some medication, some painkillers. That kicked in after 20, 30 minutes. It did help.

"Then I had to take another dose I think in the beginning of the fourth. Now that it's cooling off, I can start to feel different things. Let's see how it goes day by day."

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