Australia's hero doctor and his dive partner say the successful rescue of a young Thai soccer team from a flooded cave system "is almost beyond our imagination".
Adelaide Anaesthetist Richard "Harry" Harris and Craig Challen have also played down their importance to the daring operation, describing themselves as just a small part of an Australian contingent who all played valuable roles.
"We are humbled to have been able to provide our expertise and experience to assist in this international operation led by the Thai government," they said in a statement on Thursday.
"Our thanks and greatest admiration go the British lead divers, and support divers along the route in and out of the cave system from the EU, US, China and Australia, as well as the vast number of participants from military and civilian organisations in various support roles.
"We particularly would like to thank the players and their coach for placing their trust in us. We wish them a speedy recovery."
The pair also thanked all those who offered messages of support during the rescue which brought the last of the 12 boys and their coach to safety on Tuesday.
"The favourable outcome that has been achieved is almost beyond our imagination when we first became involved in this operation," they said.
Dr Challen's partner said the retired Perth vet had initially doubted the huge undertaking would end well.
"He did hold concerns for the whole situation," Heather Endall told ABC radio.
"I think he went over there with a bit of a pessimistic view - he thought it was going to be a real challenge to get the boys out alive.
"He didn't actually display any regard for his own safety."
The Aussie dive buddies were preparing to head to the Nullarbor for a holiday when Dr Harris called to change their plans.
The pair were on their way to Thailand within an hour.
Dr Harris had been asked for by name because of his 30 years experience as a cave diver and also his expertise as a medical retrieval specialist with South Australia's MedSTAR service.
Dr Challen has also explored Australia's longest and deepest underwater caves, Cocklebiddy and the Pearse Resurgence, and is one of only a few to dive some of the country's deepest wartime wrecks.
Prime Minister Malcolm Turnbull told the ABC that Dr Harris had spoken of the extraordinary heroism of the boys and divers, which would stay with him.
"I am inspired by the remarkable international cooperation," Mr Turnbull said.