The Serbian star was freed from an immigration detention centre yesterday after an appeal hearing overturned his visa cancellation.

However, Djokovic - who is preparing to compete at the Australian Open - is now facing fresh claims that he lied on his form to enter Australia.

Djokovic has been accused of incorrectly filling out his Australia Travel Declaration (ATD) document, which was released during yesterday’s appeal hearing.

When asked whether he had travelled or will travel in the 14 days prior to their flights to Australia, "No" was ticked on Djokovic’s ATD.

The form then read: "Giving false or misleading information is a serious offence.

"You may also be liable to a civil penalty for giving false or misleading information."

Djokovic confirmed at the court hearing that he had "authorised" his agent to submit his ATD "on or about 1 January".

Several social media posts have suggested that Djokovic was in Belgrade on Christmas Day and Spain on New Year’s Eve before landing in Melbourne on January 5.

Djokovic informed immigration officers that his agent had completed the ATD before submitting it to Tennis Australia in order to gain a medical exemption from vaccination requirements.

However, the border officer said the cancellation was made "based on information the visa holder provided".

"The visa holder stated that Tennis Australia facilitated his medical exemption from COVID-19 vaccination requirement and completed the Australia Travel Declaration on his behalf," the officer said.

"I consider that Tennis Australia would have facilitated his medical exemption and Australian Travel Declaration based on information the visa holder provided to them.

"As such, I don’t consider these constitute extenuating circumstances beyond the visa holder's control. 

"Based on the above, I apply significant weight in favour of visa cancellation for this factor."

Federal Circuit Court Judge Anthony Kelly ruled that Djokovic was not given enough time to speak with his legal team in response to the decision to revoke his visa.

Kelly claimed the visa cancellation under section 116 of the Australian Migration Act was "unreasonable" and ordered for his immediate freed from detention.

His release sparked celebrations among his supporters in Serbia and outside the court.

The 34-year-old said he was "pleased and grateful" the court overturned his visa cancellation in a post on social media where he included a picture of himself and his team on the court at Melbourne Park.

Australian Immigration Minister Alex Hawke could still exercise the power to cancel Djokovic’s visa again, but a decision has yet to be made.

The controversy surrounding Djokovic’s participation at the Australian Open has also created a diplomatic row with Serbian President Aleksander Vucic hitting out at Australia for the "harassment of the world’s best tennis player".

It has been confirmed that Australian Prime Minister Scott Morrison has contacted Serbian counterpart Ana Brnabić to discuss the Djokovic saga.

"The PM explained our non-discriminatory border policy and its role in protecting Australia during the Covid-19 pandemic," a spokesperson for Morrison said.

"They both agreed to stay in contact on the issue and to further strengthening the bilateral relationship."

The Association of Tennis Professionals (ATP) said the Djokovic situation had been "damaging on all fronts" and called for greater clarity on rules to enter Australia.

"Complications in recent days related to player entry into Australia have however highlighted the need for clearer understanding, communication and application of the rules,” a statement from the ATP read.

"In travelling to Melbourne, it’s clear Novak Djokovic believed he had been granted a necessary medical exemption in order to comply with entry regulations.

"The series of events leading to Monday’s court hearing have been damaging on all fronts, including for Novak's well-being and preparation for the Australian Open.

"Player medical exemption requests are made independently of ATP, however we have been in constant contact with Tennis Australia to seek clarity throughout this process.

"We welcome the outcome of Monday’s hearing and look forward to an exciting few weeks of tennis ahead."

The ATP said three of the top 100 men's singles players are unvaccinated - one of whom is Djokovic.

"ATP continues to strongly recommend vaccination for all players on the ATP Tour, which we believe is essential for our sport to navigate the pandemic," the body added.

"This is based on scientific evidence supporting the health benefits provided and to comply with global travel regulations, which we anticipate will become stricter over time."

Djokovic is tied for the record number of men's singles Grand Slam titles on 20, alongside Spain's Rafael Nadal and Switzerland's Roger Federer.

The Australian Open is scheduled to run from January 17 to 30.