Hailed as one of the greatest tennis players of all time, Novak Djokovic is at the centre of fresh controversy after writing "Kosovo is the heart of Serbia. Stop the violence" on a camera at the French Open after his first round match in response to clashes flaring up in northern Kosovo fuelled by ethnic tensions.

"Kosovo is our cradle, our stronghold, centre of the most important things for our country," he told reporters in Paris.

The 22-time major winner is no stranger to causing a stir on and off the court.

AFP Sport looks at some of the incidents that have dogged the career of the former world number one:

- Deported from Australia -

The famously unvaccinated Djokovic arrived in Melbourne to play the 2022 Australian Open claiming he had a valid medical exemption from the vaccine. However, after a protracted legal fight, his visa was cancelled on "health and good order grounds" before he was deported.

Serbian President Aleksandar Vucic accused the Australian government of conducting a "witch hunt" against Djokovic.

As Djokovic left the country, he said: "I respect the court's ruling and I'll cooperate with the relevant authorities in relation to my departure from the country.

"I am uncomfortable that the focus of the past weeks has been on me and I hope that we can all now focus on the game and tournament I love."

He returned to Melbourne in January this year where he swept to a 10th Australian Open title.

His refusal to be vaccinated also led to him being banned from the 2022 US Open.

- US Open default -

Djokovic saw his 2020 US Open title hopes dashed when he was sensationally disqualified from his last-16 match against Pablo Carreno Busta after accidentally hitting a female line judge in the throat with a ball.

The Serb had lashed out in frustration after dropping serve in a match played on an empty Arthur Ashe Court where fans were banned due to the pandemic.

"This whole situation has left me really sad and empty," Djokovic said in a statement.

"I checked on the linesperson and the tournament told me that thank God she is feeling OK. I'm extremely sorry to have caused her such stress. So unintended. So wrong."

- Covid tour -

In the midst of the pandemic in 2020, and with professional tennis shut down, Djokovic organised the Adria Tour, a series of exhibition events in the Balkans.

However, the tournament was abandoned in Zadar in Croatia after Bulgarian player Grigor Dimitrov tested positive for coronavirus.

Djokovic and his wife Jelena, as well as fellow players Viktor Troicki and Borna Coric, also went on to reveal positive tests.

"I know there has been some criticism, especially from the West," Djokovic said. "Why do we have spectators there? Why is there no social distancing? Why is this kind of event taking place while there is a serious pandemic in the West?," said Djokovic.

"It is not easy to explain to people that the situation in the United States or Great Britain is completely different from that in Serbia or the surrounding countries."

- Pain barriers -

Djokovic has long faced accusations that he exaggerates injuries in matches.

At the 2008 US Open, he took two medical timeouts in a gruelling five-set win over Tommy Robredo.

Quarter-final opponent Andy Roddick then mockingly listed Djokovic's injuries to include "two hurt ankles, bird flu and SARS!"

Djokovic defeated the American and hit back in his post-match, on-court interview.

"Well, obviously Andy was saying I had 16 injuries last match... and obviously I don't," he said.

At the 2020 French Open, vanquished quarter-final rival Carreno Busta was dismayed to see the trainer called to tend to the Serb.

"Every time a match gets complicated he asks for medical assistance," said the Spaniard.

- Water way to go -

Djokovic came under fire when he claimed it was possible to alter the composition of water and food through positive thinking.

In an online exchange with 'wellness guru' Chervin Jafarieh, he said: "I've seen people and I know some people that through energetical transformation, through the power of prayer, through the power of gratitude, they manage to turn the most toxic food or the most polluted water, into the most healing water.

"Because water reacts and scientists have proven that molecules in the water react to our emotions to what is being said."

Former player and respected TV pundit Mary Carillo told The Tennis Channel that she hoped Djokovic would back down on his claims.

"I'm very disturbed that Djokovic and that other guy are saying you can change toxic water to drinking water," she said. "This is dangerous stuff."

dj/gj