Former world heavyweight boxing champion failed test on the day of his loss to Fabio Wardley, promoter says.

New Zealand’s former heavyweight world champion Joseph Parker failed a drug test on the day he fought the United Kingdom’s Fabio Wardley last month, manager Frank Warren’s Queensberry Promotions has confirmed.

British media had previously reported that the 33-year-old had tested positive for traces of cocaine and could face a lengthy ban from the sport.

“The Voluntary Anti-Doping Association (VADA) last night informed all required parties that Joseph Parker returned an adverse finding following an anti-doping test conducted on the 25th October in relation to his bout with Fabio Wardley,” Queensberry said in a statement on Friday.

“While the matter is investigated further, no additional comment will be made at this time.”

Wardley stopped fight-favourite Parker in the 11th round at London’s O2 Arena in the WBO “Interim” clash to earn the right to challenge Ukraine’s undisputed world champion Oleksandr Usyk.

The British Boxing Board of Control (BBBofC), which would decide the length of any ban, could not be reached for comment on the next steps and the length of any potential ban.

The UK Anti-Doping Agency (UKAD) would not comment, as is its standard practice.

Parker has not yet commented on his social media channels.

British boxer Liam Cameron was banned for four years after he tested positive for benzoylecgonine, a metabolite of cocaine, in 2018.

Parker won the WBO heavyweight title in 2016 by defeating Mexican Andy Ruiz for the vacant belt. He lost the title to Anthony Joshua of the UK in 2018.

He had held the WBO interim heavyweight title since March last year after defeating China’s Zhang Zhilei.