Former Wallabies hooker Nathan Charles has revealed he has been diagnosed with motor neurone disease (MND), just eight years after retiring from professional rugby.

The 37-year-old made four appearances for the Wallabies between 2014 and 2015, including a 12-12 draw against New Zealand.

Charles revealed the diagnosis during an interview with former Wallabies lock Justin Harrison, saying he had spent months undergoing tests and seeing doctors as his health deteriorated.

“For a long period there I just didn’t know what it was,” Charles said.

“Then recently, in the last few weeks, I was actually diagnosed with motor neurone disease, which has been extremely challenging and overwhelming.”

Charles said he understood the seriousness of the diagnosis, adding that there is currently no cure for MND.

Charles overcame cystic fibrosis

The diagnosis is another major health challenge for Charles, who had already overcome extraordinary odds during his rugby career.

He was diagnosed with cystic fibrosis when he was just three months old and was reportedly told that he might not live beyond the age of 10.

Despite the condition, Charles went on to establish a professional rugby career spanning Australia and England.

He played Super Rugby for the Western Force and Melbourne Rebels before continuing his career in England with Gloucester, Bath and Wasps.

Charles retired from professional rugby in 2018 after a career that included his four Wallabies caps.

He later moved into rugby administration, serving as chief executive of Rugby Western Australia and becoming involved with Sydney University Rugby Club.

MND is a group of progressive neurological conditions that affect the motor neurones responsible for controlling voluntary muscle movement. Amyotrophic lateral sclerosis (ALS) is the most common form of MND.

Charles is now facing the condition after spending much of his life dealing with cystic fibrosis.

He described the situation as particularly difficult given that he had spent his life overcoming his first serious illness.

“I was born with a life-threatening illness. I’ve given that a red-hot crack. Now this other thing comes along,” he said.

The rugby community has already rallied around Charles.

The Wallabies posted a message of support, while captain Harry Wilson told the former international that the team would be with him through the difficult period ahead.

Charles joins a number of prominent rugby figures who have faced MND.

Former England captain Lewis Moody was diagnosed with the disease last year, while former Scotland international Doddie Weir and rugby league star Rob Burrow both died after battles with MND, as did Springbok great Joost van der Westhuizen.