Heavyweight boxing contender Dillian Whyte reportedly tested positive for a banned substance just three days before besting Oscar Rivas to earn a possible title shot.

The British boxer, whose July 20 win over Rivas at London's O2 Arena put him in line for a fight against WBC belt-holder Deontay Wilder, could face a suspension - especially since he was suspended for two years In 2012 after testing positive for Methylhexaneamine. The latest positive test was reported by Thomas Hauser, of Boxing Scene. The British Boxing Board of Control and Whyte's promoter, Eddie Hearn, were notified prior to Saturday's fight, but the BBBC permitted the match to go on, according to the report. Whyte overcame a ninth-round knockdown to win a unanimous decision.

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UK Anti-Doping (Ukad) told the BBC it would not comment. Whyte may now ask for a 'B sample' to be analyzed. If that also tests positive, he can request an appeal.

The 31-year-old Whyte, who boasts a 26-1 record with 18 knockouts, has long been eager for a title shot.

"Deontay Wilder has ducked once again," Whyte wrote earlier this year in a column for TalkSport. "If people don't believe he's running from the big fights by now, then I don't know what to tell them... I want Wilder bad, especially after all of this nonsense. After all the time I've spent chasing the WBC belt, I want that above all else."

Hearn, issued a statement on Twitter regarding the report.

"Further to reports I can confirm that both Dillian Whyte and Oscar Rivas were subject to extensive VADA and UKAD testing for their bout," Hearn wrote. "Both fighters were cleared to fight by both bodies and the BBBofC."

Yvon Michel, the promoter for Rivas, who was also tested prior to Saturday's fight, said he only learned of the development through the Boxingscene.com report.

"We have learned this information like everybody else on Boxingscene.com yesterday evening. I have not heard from any concerned parties yet to get confirmation or counter," he said. "I will wait to know more before any more comments. Nobody from our team was aware of the situation before the fight or after the fight up to this moment."

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