Vic Cornell, 95, was out chopping wood for the fire when a piece "chipped up" and hit him in the nose.
He had to go to the Royal Melbourne Hospital for treatment, and it was there he suspects he contracted COVID-19.
"I was in the wrong place at the wrong time," he told ABC Radio Melbourne Drive presenter Raf Epstein.
Mr Cornell is now one of more than 9,000 confirmed coronavirus cases in Victoria.
With the number of active cases nearing 5,000, and deaths increasing almost daily, state authorities are becoming increasingly concerned about hospital capacity.
Earlier today, Victorian Premier Daniel Andrews announced that all but the most urgent elective surgeries would be suspended and Health Minister Jenny Mikakos struggled to hold back tears as she spoke of the "distressing situation" in aged care homes.
Well cared for
Mr Cornell has spent the last three weeks in isolation at Maroondah Hospital and said he was being well cared for.
His condition has been "up and down", but he has not needed a ventilator.
"Life goes on and never ceases to amaze me," Mr Cornell said.
"This virus has hit the world so hard and we are just part of it."
His son Russell said it was incredibly difficult not being able to see his father in hospital.
"He rang us up a couple of days ago and wanted to say goodbye. I just refused," Russell said.
After living independently his whole life, Russell said his father was "incredibly tough".
"He's got to beat it, he's got to fight it," Mr Cornell said.
"It's a tough time."
Fighting to beat the virus
Before he retired about 20 years ago, well into his seventies, Vic Cornell was a well-known tennis coach in Melbourne.
His son Russell followed him into the industry.
Mr Cornell said he was doing his best to beat COVID-19, but his age was against him.
"If I get through this it will be a miracle," he said.
Despite being seriously ill, he had hope for himself and for the future.
"Melbourne take care, fight this thing, don't let it get to you," he said.
"Let's hope out of this comes a vision for a world together, not separate.
"If I do get through this I am hoping I will be a better man than I was before."
