It is possible that up to 100 foreign athletes and team officials who came to Australia for the Gold Coast Commonwealth Games in March remain in the country without a valid visa, the Refugee Council of Australia says.
The ABC has been told a single refugee support service operating in one state has handled about 20 Commonwealth Games clients, while other sources have put the figure as high as 50.
A senior figure with intimate knowledge of those cases described it as "scores" of people who were in this situation, while another source working in the area believed it to be as high as 100.
RCA president Phil Glendenning said the high numbers were "consistent with what they've heard".
"I think your analysis is pretty well right — we don't know the exact number but I think it's certainly more than the 13 or 14 that was being kicked around," Mr Glendenning said.
"If you look at history, we would say that after the 2006 Games, 45 people stayed behind … so these things are not unusual."
Mr Glendenning said the athletes should not be used as a political football.
"We're talking about people's lives here and we have a good process in the country for dealing with people who arrive seeking asylum in this manner," he said.
"They need to have those claims properly assessed and if they've got valid claims they deserve to be protected and if they don't they need to be safely removed."
The Australian Border Force said in a statement the "vast majority" of individuals who came to Australia had departed but it was aware some had remained in Australia.
"Visa overstayers are a common feature of many major international events," the ABF statement said.
"We will not be commenting on individual cases or providing a running commentary on those remaining.
"Some individuals have already applied for other visas — those cases will be rigorously assessed in line with standard processes."
A dedicated operation has been set up by the department to "ensure those that depart Australia do so".
Those who are removed may face a three-year re-entry ban to Australia and may be slapped with the cost of their removal.