Oleksandr Usyk was falsely accused of using PEDs from a bizarre snapshot during the Tyson Fury fight.
The Ukrainian star became undisputed heavyweight champion by beating Fury on points in May, but some fans believed they had spotted Usyk using an inhaler when he was in fact kissing his crucifix.
Use of an inhaler is illegal in boxing, as fighters are only allowed to use water and Vaseline during a fight, with energy gels even banned throughout the twelve rounds.
But Usyk has since hit back at the wild conspiracy theory, furiously denying use of what would be considered a performance-enhancing drug.
“Stupid people. Listen, I never used any substance. Never. I’m clean,” he told Boxing King Media.
The cross, it’s my doping. My belief is my doping. Jesus, my family, my team, my country – this my doping.”
Several groups of fans had already come to defence of Usyk on social media, and dismissed the theory.
Footage had emerged of Usyk sat in his corner while putting an object to his mouth, which many claimed was either water or indeed his crucifix.
An inhaler is a device which is often used to treat asthma, and pumps medicine directly in the lungs to improve cardiovascular health.