Petkovic on Djokovic: "I'm not worried about his tennis, but about his health".

Novak Djokovic was forced to retire during the Australian Open semi-finals against Alexander Zverev, due to a thigh injury.

However, the Serb made a speedy comeback at last week's ATP 500 in Doha.

In a Tennis Channel podcast, Andrea Petkovic expressed her concerns: "We don't know when he was able to start training again with this muscle tear in his thigh.

Maybe it was a bit early to come back. We'll see if he talks about it.

Sometimes you can perform well in training, but in a tournament it takes a little longer.

I'm not worried about Novak in terms of tennis, I think he played very well at the Australian Open, against Alcaraz.

Some people wanted to blame Carlos, but he was just outclassed by Djokovic.

But I'm worried about his health. If he's healthy, everything will be fine."