Joseph Parker has denied taking ‘any prohibited substance’ in his first words since testing positive for cocaine.The New Zealand heavyweight was tested by the Voluntary Anti-Doping Agency (VADA) on October 25 — the day of his defeat to Fabio Wardley.Parker was stopped by Wardley in London last month and has since tested positive due to a metabolite derivative from cocaine in his systemGettyAnd it emerged on Friday morning that the 33-year-old former world champion failed the drugs test due to a metabolite derivative from cocaine in his system.Parker, 33, met Wardley at London’s O2 Arena last month, but lost the chance to face undisputed champion Oleksandr Usyk when he was stopped in the 11th round.Joseph Parker issues statement after positive test for cocaine“I want to address today’s news,” Parker wrote via social media on Friday night.“Before my recent fight, I took a voluntary test and have now been informed that it returned an adverse result. “This came as a real surprise to me. I did not take any prohibited substance, I do not use performance-enhancing drugs and do not support their use.“I am cooperating fully with the process now underway, and I am confident the investigation will clear my name.“Thank you to everyone who has sent messages of support. It means a great deal to me and my family.“When the investigation is complete, I will speak openly and answer questions.”Ex-world champion Parker could face lengthy bantalkSPORT’s Adam Catterall was one of the first to react to Parker’s positive test, which could lead to a ban from the sport.“Probably like every single other boxing fan, [it’s] incredibly shocking,” Catterall said on Friday when asked how he is feeling about Parker’s failed test.Parker is a former WBO heavyweight championGETTYHe has fought a who’s who of the world’s best heavyweight boxers, including JoshuaGetty“When any fighter fails a drug test, it is incredibly shocking and disappointing.“Knowing Joseph Parker, as we all do here at talkSPORT, with it being him connected to this, it’s even more shocking.”Frank Warren‘s Queensberry Promotions are expected to release a statement on the matter on Friday afternoon, with Parker’s camp to follow.Catterall called Parker’s behaviour ‘reckless’ but highlighted that it was hard to comment on the news, as he has spent so much time with the heavyweight boxer, and it seems incredibly out of character.VADA will now give their findings to UK Anti-Doping (UKAD) and the British Boxing Board of Control (BBBoC), who will then decide on a punishment.Cocaine is considered a recreational drug, rather than a performance-enhancing drug or PED, though Parker could reportedly still face a two-year ban from the sport.Parker thought he ‘was fine’ upon the conclusion of his fight with Wardley, who has been lined up to challenge Usyk nextGettyThe 33-year-old has said in a statement that he is confident an investigation into his failed drug test will clear his nameGettyIn 2018, British boxer Liam Cameron was banned from the sport for four years after UKAD announced he tested positive for benzoylecgonine, a metabolite of cocaine, though Cameron denied any wrongdoing.Who has Parker fought?Parker became a world heavyweight champion for the first time in December 2016 when he defeated Andy Ruiz in Auckland, New Zealand.Through victory, Parker claimed the vacant WBO heavyweight strap before defending his title twice against Razvan Cojanu and Hughie Fury.Parker then lost the chance to add the IBF and WBA titles to his collection when he suffered a unanimous decision defeat to Anthony Joshua in March 2018.After losing to Dillian Whyte in his next fight, Parker bounced back by claiming victories over names like Derek Chisora, Deontay Wilder, and Zhilei Zhang before losing a WBO interim heavyweight title bout against Briton Wardley.He was a big favourite going into his London fight with Wardley, but the heavyweight clash was stopped in the penultimate round after Wardley caught the New Zealander with a flurry of punches against the ropes. The stoppage was controversial in the eyes of some members of the boxing fraternity, but last week, BBBoC chief Robert Smith played down suggestions that the result would come under further scrutiny.Regardless of the defeat, Parker remained in high spirits in the aftermath. “At the end of the fight, I thought I was fine. But I’m not the one refereeing the fight,” Parker said.“I thought I was doing well in the fight, but I got caught, and that’s boxing. I wanted to carry on, of course.“I’m good. Congratulations to Fabio Wardley. He’s a warrior, he’s a tough man. Hopefully, we can have a rematch.“Listen, it sucks losing a fight. I won’t sit here and pretend I’m all happy, but life goes on. View this post on Instagram “Boxing is part of what I do, but I’m very blessed with a wife, kids and a happy family.“I want to go back to them, regroup and see what’s next, but it does suck.”Tyson Fury had a front-row seat for Parker vs Wardley, and paid tribute to the former’s efforts after the fight.‘The Gypsy King’ said he had the New Zealander four rounds up going into round 11.