A bizarre video of Novak Djokovic’s team preparing a drink has overshadowed the tennis superstar’s shock loss to Danish teenager Holger Rune in the final of the Paris Masters.

Rune, 19, pulled off the biggest win of his career with a stunning 3-6, 6-3, 7-5 victory over the 21-time grand slam champion, but all the talk centred on a viral clip from Djokovic’s semi-final victory.

WATCH THE VIDEO ABOVE: Djokovic’s team caught on camera preparing a secret drink.

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The video was taken during Djokovic’s win over Stefanos Tsitsipas and appears to show the Serbian’s entourage mixing a drink before realising they are being filmed.

As members of the team realise there is a camera on them they shift their seating positions to block the view.The water bottle was then handed to a ball-girl, who ran it over to Djokovic.

A viral video has emerged of Novak Djokovic’s team preparing a bottle from the stands and trying to hide it from a camera’s view before handing to a ball-girl during the Paris Masters. Credit: Screenshots

The clip has had over 3.5 million views since being posted on Twitter.

Leading tennis journalist Ben Rothernberg labelled it “bizarre” and called for more transparency about the substances players take.

“I’ve always thought there should be more transparency about the substances players take, particularly during matches, but I’ve also rarely thought anything was likely amiss,” he tweeted.

“But golly, the body language in this video is bizarre. What does the Djokovic team think needs hiding?”

“I think rivals (and the public and the officials governing the sport) should get to know (the substance). I don’t think there should be secret substances being ingested during competition.

“I’m accusing no one of anything here, but what an incredibly suspicious way to start acting when you suddenly notice that you’re being filmed. (I) Hope Djokovic and/or his team get asked about this today in Paris, and that they don’t just accept his previous “magic potions” answer.”

Djokovic was previously asked about an unknown substance he appeared to inhale at Wimbledon this year with the 35-year-old saying it was a “magic potion”.

“You’ll find out soon,” he added, “but I can’t speak about it now.”

Djokovic was not asked about the drink after losing to Rune in Sunday’s final.

Rune became the first player since the ATP rankings were launched in 1973 to have beaten five top-10 players in the same tournament, other than at the season-ending ATP Finals.

His scalps on the route to his maiden Masters 1000 final included Hubert Hurkacz, Andrey Rublev, No.1 Carlos Alcaraz – who retired injured when trailing in their quarter-final – and Felix Auger-Aliassime.

Novak Djokovic (L) congratulates his young Paris Masters conqueror Holger Rune. (AP PHOTO) Credit: AP

Now, Rune can add last year’s Paris champion Djokovic to that list, defeating the 21-time grand slam winner who had described his young opponent as the future of tennis on the eve of the final.

Rune becomes the youngest Paris Masters champion since an 18-year-old Boris Becker triumphed in 1986, and he did it the hard way too, coming from behind after Djokovic made the stronger start.

Djokovic broke Rune’s serve in the fourth game to lead 3-1 and take an early grip, soon seeing out the opening set.

Yet Rune charged 3-0 ahead in the second and grew in confidence. There was even a Djokovic-like raised fist after getting the better of his illustrious rival in one thrilling rally.

Djokovic roared ahead in the decider, but not intimidated by the occasion, Rune struck back to recover the early break.Rune then broke to lead 6-5, as his Serbian opponent became erratic.

Nobody beats Djokovic without a fight though, and the Serb carved out six chances to break back in the next game.

Rune survived them all and clinched victory on his second match point when Djokovic, who had been chasing a record-extending 39th ATP 1000 title, netted on the half-volley.

Addressing Rune in an on-court interview, Djokovic said: “You absolutely deserve this victory. What an amazing week you had.

“I’m not happy that you beat me, but on the other hand I’m happy for you because I like your personality, I think you’re a very dedicated guy that loves tennis and puts a lot of hours into hard work.

“It’s paying off for you, and I’m sure the future is bright for you and your team, so congratulations.”

Rune, who is working with Serena Williams’ former coach Patrick Mouratoglou, said: “This must be my favourite tournament now, I really enjoyed my time here.”

– with AAP

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