A case for deporting Novak Djokovic from Australia was being built on Wednesday amid a widening investigation into his coronavirus quarantine breach, false declarations within his travel documents, and unanswered questions about his positive test.

The Australian government was reportedly considering whether to use his admission he carried out an interview and photoshoot in Serbia after being told he had the disease – an offence that could carry a maximum sentence of three years in prison – to justify throwing him out of the country.

According to local media, it was also continuing to examine other alleged discrepancies related to the case.

They included his agent wrongly stating on his Australian Travel Declaration that he had not travelled in the 14 days prior to his arrival in Melbourne, and claims in German newspaper Der Spiegel suggesting his positive test may have occurred 10 days later than stated in documents submitted to his deportation court hearing.

A decision on whether to cancel Djokovic’s visa was delayed until Thursday local time at the earliest after government sources confirmed the receipt of new submissions from his lawyers as Australia’s immigration Minister Alex Hawke considered whether the world No 1 warranted being granted a medical exemption from the country’s vaccination rules.

The player also admitted to an “error of judgment” over attending an interview and photoshoot last month even after he knew he had tested positive for Covid.

In a lengthy statement on Instagram, the 34-year-old said he wanted to “address the continuing misinformation about my activities” and hoped to “emphasise that I have tried very hard to ensure the safety of everyone and my compliance with testing obligations”.

However, he admitted that he had conducted an interview and photoshoot with L’Equipe just hours after a positive PCR test, insisting he “did not want to let the journalist down”.

He also admitted that his agent had provided incorrect information to border officials regarding his previous travel before arriving in Melbourne but said it was due to “human error”.

Djokovic’s agent, Elena Cappellaro, ticked ‘No’ to the question: “Have you travelled, or will you travel, in the 14 days prior to your flight to Australia?” on his Australian Travel Declaration.

This was despite social media posts indicating that Djokovic had been in Belgrade on Christmas Day – 11 days before he arrived in Australia – but in Spain on New Year’s Eve.

Since Judge Anthony Kelly reinstated Djokovic’s visa on Monday – thus foiling initial efforts to deport him – there has been much speculation about a key detail of his defence: the certificate showing that he had given a positive PCR test in Serbia on Dec 16.

However, photographs emerged on social media of him presenting prizes to dozens of children as part of a Serbian Tennis Association ceremony on Dec 17, while L’Equipe also revealed details of its interview.

Djokovic said that he wanted to put the record straight in order to alleviate “broader concern in the community about my presence in Australia, and to address matters which are very hurtful and concerning to my family. I want to emphasise that I have tried very hard to ensure the safety of everyone.”

According to his statement, Djokovic suspected he might have Covid after attending a basketball game in Belgrade on Dec 14, as several other people had tested positive afterwards. 

As he wrote, “Despite having no Covid symptoms, I took a rapid antigen test on Dec 16 which was negative, and out of an abundance of caution, also took an official and approved PCR test on that same day.”

Djokovic then added that, before attending the prizegiving ceremony the next day, he had taken another rapid antigen test and come up negative again. Only thereafter did he leave for the event. “I was asymptomatic and felt good,” he explained, “and I had not received the notification of a positive PCR test result until after that event.”

Djokovic said that his interview with L’Equipe had been a long-standing commitment, and that he had cancelled all other activities apart from this one.

“I didn’t want to let the journalist down,” he wrote, “but did ensure I socially distanced and wore a mask except when my photograph was being taken. While I went home after the interview to isolate for the required period, on reflection, this was an error of judgement and I accept that I should have rescheduled this commitment.”

Serbian Prime Minister Ana Brnabic said before Djokovic’s admission that any failure to isolate after testing positive for Covid would be classed as a “clear breach” of the law and merit investigation, with punishment ranging between a fine and three years in prison.

Djokovic also addressed the fact that his immigration paperwork had failed to disclose the full details of his movements during the two weeks before he arrived at Melbourne’s Tullamarine Airport. 

His Australian Travel Declaration form – which he said was filled in by his agent – showed he had come from Spain but did not mention he had also been in Belgrade, the Serbian capital, on Christmas Day.

“My agent sincerely apologises for the administrative mistake,” Djokovic said. “This was a human error and certainly not deliberate. We are living in challenging times in a global pandemic and sometimes these mistakes can occur. Today, my team has provided additional information to the Australian government to clarify this matter.”

As the two sides continued their backstage machinations, Djokovic himself pressed on with preparations for the Australian Open by practising at Rod Laver Arena with 20-year-old Australian Tristan Schoolkate.