Novak Djokovic shared an frosty exchange with a tennis umpire after the Serbian was reprimanded for a shot clock violation during his Australian Open semi final, before taunting the crowd at Rod Laver Arena.

Djokovic, 35, is aiming to book his place in yet another final of his favourite grand slam, which he has won nine times, with the tennis superstar looking to win the event for a tenth time.

Seemingly cruising against United States opponent Tommy Paul at 5-1 in the first set, Djokovic was unsettled by a serve clock violation when he went to get his towel.

The serve clock gives players a maximum of 25 seconds to hit a serve after the completion of the previous point. The clock begins as soon as the umpire calls the score.

However, Djokovic appeared to argue that the clock ought to start after he collected his towel courtside - with ball kids no longer permitted to hand towels to players.

'The ball kids are not allowed to give me the towel, so tell me how it works,' he asks the umpire, who explains the rules to him. 

'It's the first time I've been to the towel this game, and you start the clock before I touch the towel. Well done.'

The typically ice-cool Djokovic lost his head after that moment, with Paul winning nine points in a row before clawing the first set back to 5-5. He eventually composed himself and took the first set 7-5 to a chorus of boos from the crowd.

Playing up to his pantomime villain status, Djokovic put his finger behind his ear to taunt the spectators at Rod Laver Arena.  

Djokovic has endured his fair share of on-court blow ups at this year's tournament. During his quarter final win over Andrey Rublev, he demanded that a fan be warned after he was heard shouting 'send him home Rublev' - referring to his deportation saga in 2022.

In his second round match against Enzo Couacaud, he said that a quartet of fans dressed in Where's Wally outfits were 'trying to get in my head' with constant heckles.

'The guy's drunk out of his mind, from the first point he's been provoking me,' he said. 'He's not here to watch tennis. He just wants to get in my head.'

Djokovic also asked the umpire: 'What are you going to do about it? Why don't you get security to get him out of the stadium?' 

Away from the court, the spotlight has been on Djokovic in the past 48 hours. His father, Srdjan, was filmed posing with supporters of Russian president Vladimir Putin outside Melbourne Park on Wednesday night.

'So there is no disruption to tonight's semi-final for my son or for the other player, I have chosen to watch from home,' he said in an emailed statement on Friday. 

'I had no intention of causing such headlines or disruption.

'I was outside with Novak's fans as I have done after all of my son's matches to celebrate his wins and take pictures with them. I had no intention of being caught up in this.

'My family has lived through the horror of war, and we wish only for peace.

'I wish for a great match and I will be cheering for my son, as always.'