Brown had 15 plates and 64 screws in his face and suffered “about 20” concussions by the end of his career, while he also dealt with headaches and balance issues.

7NEWS.com.au is not suggesting a link between the concussions and his brain tumour.

But the head knocks defined the latter stages of his stellar career as he bravely fought on for a Brisbane side that struggled to contend for finals.

His last concussion came from a knee to the head in an accidental collision with GWS player Tom Bugg.

Despite friends and premiership coach Leigh Matthews urging him to retire, the decision only came when Brown asked his then four-year-old daughter Olivia about whether he should keep playing.

“She looked at me in the eyes and said ‘no, you can’t play footy any more. You can only play footy if the Lions come down and play on the grass with us at our place’,” Brown wrote in his autobiography.

“That’s when it finally became real that I was going to retire. I finally acknowledged that I was still forgetting stuff, still had headaches and still had problems with my balance.”

Brisbane doctor Paul McConnell had previously feared for Brown’s life when he suffered a friendly-fire concussion in 2011.

“I honestly thought he was going to die. Thankfully an ambulance arrived very quickly. He didn’t move at all until we started moving away from the Gabba,” McConnell said in the book.

“I would say he was totally and utterly unconscious for at least five minutes, maybe six or seven. It was one of the worst injuries I have seen in my life.