James Harrison has retired after saving the lives of more than 2.4 million babies by donating his blood over the past 60 years.
The "man with the golden arm", as he has been dubbed, told The Sydney Morning Herald that his retirement was "a sad day" and "the end of a long run".
Mr Harrison's blood contains an extremely rare antibody in his plasma which is used to develop medicine to prevent newborns from dying from Rhesus disease.
The medicine, anti-D, is given to pregnant mothers whose rhesus negative blood is at risk of attacking her baby's rhesus positive blood.
At 81 years of age, Mr Harrison has made his 1,173rd and final donation – meaning he has provided more than a thousand bags full of his life-saving blood.
He holds the Guinness World Record for the number of donations made, and the Australian Red Cross Blood Service said: "His kindness leaves a remarkable legacy, and he has put the challenge out to the Australian community to beat it."
In 1999, Mr Harrison received the Medal of the Order of Australia for his "incredible and ongoing support of the blood service and anti-D programme", the organisation stated.
He is one of only 50 people in Australia believed to have these antibodies in their blood.
"I hope it's a record that somebody breaks, because it will mean they are dedicated to the cause," Mr Harrison said.
The super donor began donating blood after he underwent major chest surgery at just 14 years old and depended on the blood of strangers to save his life.
Over a decade after he started donating blood, it was discovered that his contained the vital antibody needed to make the anti-D medicine.
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Mr Harrison was happy to continue to donate and switched from plain blood to plasma donations in order to help as many people as possible.
He has now passed the age-limit in Australia to continue giving blood, although he says he would do so if they would let him.