'Unbelievable behaviour': Novak Djokovic unleashes in ugly meltdown

Novak Djokovic (pictured right) leaving after his victory and (pictured left) smashing his racquet at the Belgrade Open.
Novak Djokovic (pictured) lost his temper and smashed his racquet during the second round at the Belgrade Open. (Twitter/Getty Images)

World No.1 Novak Djokovic has unleashed in his second round of the Belgrade Open after smashing his racquet during a mid-match meltdown.

Djokovic swept past lucky loser Mats Moraing 6-2, 7-6 (7-4) to book his place in the quarter-finals of the Belgrade Open.

WOW: Tennis world stunned by Osaka's shock French Open announcement

EPIC: Tennis world erupts over Ash Barty and Naomi Osaka photo

But the World No.1, in his first match back since his defeat to Rafael Nadal at the Italian Open final, was pushed in the second set as he struggled to find a rhythm to close out the match.

This prompted a frustrated Djokovic to erupt after he hit a forehand halfway down the net.

Djokovic proceeded to smash his racquet three times into the red clay, before returning to his chair in between games.

The chair umpire handed Djokovic a point penalty for the outburst, but the 18-time Grand Slam champ used the release of tension to hold his nerve and finish the match in a tiebreak.

Some fans took to social media to criticise the behaviour, while others said it was part of Djokovic's game to let out unwanted frustration.

Djokovic laments missed opportunity

Djokovic, who turned 34 on Saturday, was full of praise for Moraing and said he was frustrated he couldn't close out the match against a 'courageous' opponent.

"I was twice a break up in the second set, so I maybe could have finished out the job earlier," Djokovic said, after his win over German Moraing.

"But credit to him for fighting, for playing really well, for playing very courageous, very bold tennis."

Djokovic will take on Argentina's Federico Coria for a spot in the last four.

In other results on Tuesday, Croatian qualifier Alex Molcan crushed Pedja Krstin 6-0 6-0 to secure the first double-bagel of 2021 on the ATP Tour.

Molcan will face Fernando Verdasco next after the veteran Spaniard accounted for fourth-seeded Frenchman Adrian Mannarino 7-6 (7-4), 6-0.

with AAP

Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:

Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.