One of the Brisbane Lions's Club doctors believed Jonathan Brown was about to die after his horrifying 2011 collision with teammate Mitch Clark.

The Brisbane Lions legend has 15 plates and 64 screws in his face after a series of worrying head knocks and concussions that ultimately ended his career.

His biography Jonathan Brown: Life and Football charts in forensic detail the aftermath of his 2011 collisions with Fremantle’s Luke McPharlin and Clark later that year, both at the Gabba.

Brown was effectively forced to retire midway through 2014 after another collision — this time with Greater Western Sydney’s Tom Bugg.

In an extract from his book released to the Herald Sun, Brown writes of lying unconscious on the field after colliding with Clark, with his wife Kylie “gripped by a feeling I was going to die”.

Author Adam McNicol quotes Brisbane club doctor Paul McConnell who described his fear Brown would be killed because of the collision.

“To sum it up in layman’s terms it was clear that something was seriously wrong with him,’’ McConnell said.

“He started what is called Cheyne-Stokes respiration which is an irregular breathing pattern often seen in the last days of a patient’s life.

“I have had a lot of experience working in intensive care and accident and emergency units and 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.

“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. In all honesty I wasn’t confident that he was going to survive until he started moving his limbs as we were driving up the ramp into the Princess Alexandra Hospital.”

Brown had three facial surgeries within the space of 12 months, then was concussed in Round 13, 2014 after accidentally colliding with Bugg’s knee.

Despite failing two concussion tests and being told by close friends and former coach Leigh Matthews to retire, he could not make that decision.

The following weekend he asked young daughter, Olivia, if she wanted her father to keep playing.

“She looked at me in the eyes and said, “No, you can’t play footy any more,’’ he writes.

“You can only play footy if the Lions come down and play on the grass with us at our place’.

“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.”

Jonathan Brown: Life and Football will be released on July 29 through Penguin Books.