Australian Ninja Warrior competitor and former NRL player Eloni Vunakece wants more evidence about the fatal effects of game concussions.

Mr Vunakece was forced to retire at the end of last year because of repeated concussions after making his NRL debut when he was 28-year-old.

The Fijian international says he will donate his brain to concussion research following the discovery of a deadly brain condition in two former NRL players.

Mr Vunakece tells Natalie Peters and Erin Molan he won’t make any judgements until there is concrete evidence.

“I’m still going to sit on the fence about it all.

“If or when that evidence ever does come to be concrete… I’ll worry about it then.”

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