But in a stunning show of courage and determination, Purtell has continued playing football in the bush – while he has been undergoing an intensive course of chemotherapy.
Purtell, 36, is coach of NSW Group 9 club Albury Thunder and kept the illness a secret from the local footy community.
"I felt a lump in my throat in March and about six weeks later, after all sorts of tests, it was diagnosed as Non-Hodgkin's lymphoma – an aggressive cancer that attacks the body's vital organs," he told Wide World of Sports.
"It was pretty scary but the one good thing was that it was only stage two and hadn't spread so that was a small victory.
"I underwent six lots of chemotherapy and they really knocked me around for 10 days or so each time – it's not something I enjoyed.
"But I still love the footy and saw it as a welcome distraction from all my worries.
"I couldn't train much before games because I felt too crook and that made it tough.
"I sat on the bench and planned to play only 20 minutes or so. But I couldn't help myself – most weeks I played around 60.
"I'm finished with the chemo now but have a four-week radiation cycle ahead of me – hopefully that will be the end of it."
Purtell had planned a charity match this weekend with proceeds to go to the Albury Regional Cancer Centre to show his gratitude for helping save his life.
But the match – and the rest of the Group 9 season – has been cancelled due to COVID-19.
"It's a real shame because they have been great to me – hopefully I can find another way to help them out," he said.
The cancer wasn't the first health scare for Purtell, an honest toiler who played over 200 first grade games in Australia and England.
"I had a heart attack while I was at Bradford in 2012," he said.
"But I got over that and got back on the field – you just have to keep going.
"I'd like to think I've had more than my fair share of health scares and can now live a long, healthy life."
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