Kiwi heavyweight boxer Joseph Parker is protesting his innocence, after admitting he failed a drugs test on the day of his defeat to British boxer Fabio Wardley last month in London.

News outlets in the UK said the former world champion tested positive for cocaine.

Parker says it was a voluntary test and the adverse result was 'a real surprise'.

Former professional boxer Junior Fa says this development has come as a shock to New Zealand's wider boxing community.

"This is a bit of a shock in terms of lifestyle choice - and from the boxing world, Joe Parker is very, very beloved, everyone loves him. This comes as a shock to everyone."

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