Nine Australians have been fined about AU$4100 (NZ$4300) each for tampering with their Olympic accreditation but have avoided a conviction and potential jail sentence.
But the Australian Olympic Committee says it's not the fault of the athletes, saying they are disappointed the group was detained by Brazilian authorities for about 10 hours.
However, Australia's chef de mission Kitty Chiller says the athletes knew their accreditations had been tampered with ahead of trying to enter an Olympic venue to watch the Boomers' basketball semi-final on Friday night (local time).
"Very disappointed that our athletes had to go through what they did go through last night," Ms Chiller told reporters on Saturday.
"I think it's very important to note that the athletes were definitely not at fault.
"And we have, and continue to, provide as much support and counselling to them and their parents and that has already commenced.
"I can't be any more specific at this point in time until we have completed our own investigation."
International Olympic Committee president Thomas Bach was told of the incident on Saturday morning.
"We respect fully here the laws in Brazil and the legal authorities," Mr Bach told reporters.
"With regard to the Australian swimmers (sic) ... it happened obviously last night, I got only information this morning, I cannot yet comment."
Australia's Ms Chiller, asked how it could not be the fault of the athletes, replied: "I will repeat: We will complete our own internal investigation about how the circumstances arose that the athletes arrived in the venue with accreditations with a different access code to their own."
Ms Chiller again repeated the same answer when asked if there were other people involved in the tampering.
Stickers were placed over the original accreditations of the athletes.
"It's unfortunately a practice that has been traditional not only in Australia but other countries as well for many Olympic Games, putting a sticker on your accreditation with another venue access code on it," Ms Chiller said.
The athletes must pay the fines - 10,000 reais (AU$4100) each - before they are allowed to leave Rio, with their passports surrendered to a Rio court.
But the AOC said it would pay the fines and hoped the athletes would be able to leave Rio with the rest of the Australian team on Monday night.
The nine Australians, charged with falsifying a document, have also been placed on a two-year good behaviour bond.
They are cyclists Ashlee Ankudinoff and Melissa Hoskins, rugby sevens player Ed Jenkins, archers Alec Potts and Ryan Tyack, rowers Olympia Aldersey, Fiona Albert and Lucy Stephens, and hockey player Simon Orchard.
Cyclist Matthew Glaetzer was not charged but was detained as a witness.
The athletes were charged after attempting to gain entry to Olympic venue Carioca 1 for the Australian men's basketball semi-final against Serbia on Friday night.