Rugby league legend Wally Lewis has revealed he has been diagnosed with probable chronic traumatic encephalopathy, a condition brought on by head knocks in his stellar sports career.

Lewis, dubbed “the King” for his astonishing feats on the field, has revealed how his likely diagnosis with the dementia-related condition forced him to quit his TV role with the Nine Network in Queensland in January.

“For a lot of sports guys, I think most of us take on this belief that we’ve got to prove how tough we are, how rugged, and if we put our hands up and seek sympathy, then we’re going to be seen as the real cowards of the game,” Lewis told Nine’s 60 Minutes on Sunday.

“But we’ve got to take it on and admit that the problems are there.”

The 63-year-old said scans of his head were so devastating, even his doctor had tears in her eyes as she relayed what they meant.

“She just said, ‘I don’t think I’ve seen one like this’ and just kept talking and saying that there had been other ones of concern,” Lewis said.

Chronic traumatic encephalopathy (CTE) is caused by repeated blows to the head – an athlete doesn’t even need to be concussed for the condition to develop.

Lewis is just the latest in a growing string of Australian sports greats to reveal they have had a likely diagnosis.

Earlier this year, Australian rules great Gary Ablett Snr announced he is suing the AFL and his two former clubs over compensation for ongoing damage suffered from concussions.

And in March, a class action led by former Melbourne player Shaun Smith, Adelaide Crows premiership player Darren Jarman and the family of the late Shane Tuck was launched.

“There’s dozens, possibly hundreds of other football players, both young and old, who are struggling with neurological issues post career that we really need to be acknowledging,” neuroscientist Dr Alan Pearce told The New Daily.

He said it had been known for decades that repeated hits to the head can lead to pathological damage, but most awareness had surrounded boxing. The first case of neuro-degenerative disease was identified outside of boxing only in the early 2000s.

Lewis admits suffering multiple head knocks in a decorated career that netted eight State of Origin player-of-the-match awards and led to the league Immortal being cast in a bronze statue outside Suncorp Stadium.

CTE can only be diagnosed for certain after death, so Lewis will never know for sure if he does have it.

But his neurologist, Dr Rowena Mobbs, said she was about as certain as she could be that he has developed it after years of repetitive head trauma through tens of thousands of tackles.

“You could interpret it as guesswork, but it’s educated guesswork by a specialist in dementia,” she told 60 Minutes.

“It does look like CTE. There’s plenty of evidence pointing towards that – I’m 90 per cent certain this is the case.”

Lewis said issues with his short-term memory prompted him to get further tests.

“I remember Wally picked me up, he talked to me about something and we were driving along and about three minutes later he said – it was as if he’d never told me – told me the same story,” Lewis’s partner, Lynda Adams, told 60 Minutes.

“I said ‘OK’ and then, about three or five minutes later, [he] told me the same story.”

Lewis said it was an embarrassing moment.

“You feel your face go red and you think, ‘well, there’s just another one’,” he said.

Lewis – who now struggles to even remember the name of the condition he has – said he had no regrets about his 14-year professional rugby league career, despite the diagnosis. But he said he might have played “a little bit differently”.

“I didn’t go in there to pick up the concussions. Nor did I think about evading them,” he said.

“I was playing footy for the love of the sport. It really has been my life. And again, I’m not seeking sympathy.

He said he had loved rugby league, and felt privileged to have played at the level he had.

“When you go out there and you’re wearing the representative jerseys, particularly the one for Australia, you feel 10-foot tall and bulletproof,” he said.

“Well, you might think you are but actually you’re not.”