As Melbourne gears up for the Australian Open, the tennis world faces the prospect of a competition-eve visa controversy for the second year in a row.
This time, the controversy centres on Italian player Camila Giorgi, who is reportedly under investigation for allegedly using false COVID-19 vaccination certification.
The claim raises questions about her entry into Australia for last year's Open — when players were required to show proof of vaccination.
Here's what we know about the situation.
What are the allegations?
The claims, which Giorgi is yet to publicly address, were raised by media in the Italian player's home country.
Doctor Daniela Grillone is under investigation there for allegedly delivering fake COVID-19 vaccinations to patients with their knowledge.
According to Italian media, Dr Grillone recently identified Giorgi as a patient, stating she was not vaccinated against COVID-19.
Last year, when proof of COVID-19 vaccination was required to enter Australia, Giorgi competed in the Australian Open.
The allegation now raises questions over whether Giorgi used a false COVID-19 vaccination certificate to enter Australia ahead of the tournament.
The Women's Tennis Association [WTA] has not taken any action against Giorgi at this stage.
"We are aware of the allegations and are currently monitoring the situation and any investigations that that may be brought forward," the WTA said in a statement.
Giorgi is in Australia, where she is listed to compete at the Australian Open this month.
People arriving in Australia are no longer required to demonstrate proof of COVID-19 vaccination.
Could Giorgi be forced to leave Australia?
A spokesperson for the Department of Home Affairs declined to confirm whether officials were investigating Giorgi's situation, citing privacy obligations.
"All allegations of fraudulent or falsified information relating to a visa application are assessed to determine the veracity of the claims," the spokesperson said.
"If a document submitted in support of a visa application is found to be fraudulent, the visa may be refused or cancelled."
Immigration lawyer John Findley said in cases such as this, immigration officials would investigate the allegations before any action was taken to ensure they were not the result of "malicious gossip".
"The department, being delegates of the minister, would write to the person who provided the allegedly false information and ask them to explain, or justify, or demonstrate the document was a genuine document and not a bogus document," he said.
"And they would also at the same time give the visa applicant the opportunity to withdraw the application."
He said if the Home Affairs minister assessed a document as bogus, the department could ask any visa applicant in the country to leave and apply a three-year ban on re-entry.
Mr Findley said this kind of provision could be used against a person based on historical information about past visa applications.
That administrative course of action to cancel a visa could be challenged by the visa applicant, as was the case with Novak Djokovic last year when the unvaccinated tennis star's visa was cancelled on health and good order grounds.
"A judicial review could be sought for that decision or an administrative review through the Administrative Appeals Tribunal … most likely it's going to go to the court," Mr Findley said.
While providing false information on a visa application could also attract criminal penalties, Mr Findley said it was rare for the government to pursue charges.
What has Tennis Australia had to say?
Tennis Australia CEO Craig Tiley was wary of engaging in detailed commentary about the allegations when asked on Sunday morning.
"I think there's still a lot to be uncovered on that and I think that's going to be ultimately up to their family and the relevant authorities including the tour," he said.
"I don't really know any further detail."
