Researchers have found damage in the brain of late Aussie sports star Jacinda Barclay.
The Australian baseball, AFLW and American football star died last year at age 29 after a battle with mental illness.
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The AFLW star became the first Aussie female athlete in a contact sport to donate her brain to the Australian Sports Brain Bank.
And according to The Guardian, researchers have found neurological damage that they described as a “ticking time bomb”.
Researchers have uncovered a degradation in Barclay's cerebral white matter, which has previously been associated with sports like American Football.
It is understood to be the consequence of repetitive head injuries and has been linked with mental illness.
Researchers said the changes in white matter are unusual for a person so young.
“The vessels in the white matter had changes that you often see in elderly people, but not in someone of Jacinda’s age who is in peak physical health,” Michael Buckland, the executive director of the Australian Sports Brain Bank, told The Guardian.
“An elite athlete shouldn’t have those changes.
"There was some evidence of white matter injury around those altered vessels.
"I hadn’t noticed that before in other subjects, but we haven’t had many athlete donors as young as Jacinda before.”
Barclay hadn't suffered any significant concussions in her career, making the discovery somewhat alarming.
"Barclay did not have a substantial clinical history of concussion, and her brain did not show evidence of her having sustained a concussion in the weeks before she died," the report says.
Her donation has been hailed as “a defining moment towards balancing gender equity in sports concussion research”.
Global sport rocked by death of Jacinda Barclay
Barclay represented Australia at five baseball World Cups and also featured in the short-lived Legends Football League.
"The news is devastating and our hearts are breaking,” Steph Mur - a former teammate of Barclay's at the Chicago Bliss - wrote.
"Jacinda lived a life that most people could only imagine. She was an elite multi-sport athlete constantly shredding boundaries around the world.
"She was every coach and players’ dream- a fearless leader full of positivity, vast knowledge, eagerness to grow and dedication to every team member. More importantly, she was an all-round badass person."
Kayla Lee, another former Bliss teammate, provided a tragic insight into Barclay's life and said the 29-year-old was "fighting demons none of us knew about".
“You never really know what someone is going through. This morning I woke up to the devastating news that we had lost one of the most vibrant, positive and spirited souls on this planet," Lee wrote.
“Cinda has been one of my closest friends since we met 7 years ago training and playing in the LFL.
"She was my quarterback and always had my back. We trained hard, laughed hard and sometimes partied hard together.
“She was a naturally talented multi-sport athlete, who was driven, ambitious and a leader that was fighting demons none of us knew about. I am absolutely heartbroken and in complete shock.”
Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:
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