The infamous Runit Championship League made its debut in Auckland this week and one former NRL star is defending the event.
The sport involves rival participants running straight at each other at full force - and many leading neuroscience experts have condemned it and outlined the risks.
George Burgess says the competitors know what they're doing and they're not aiming to hurt each other.
"Every sport that we have in our society is to remind us of our warrior past and to simulate warfare in a safe way - and that's exactly what we do."
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