Anthony Joshua and Kubrat Pulev both passed their final drug tests following their heavyweight clash last month. Joshua stopped his mandatory challenger in the ninth round to retain his three world titles in London.
And the Voluntary Anti-Doping Ageny (VADA) has confirmed both fighters' final samples came back clean. Joshua insists his opponents enrol with VADA for a 10-12 week period before they meet in the ring.
That process saw Jarrell Miller miss out on a shot at the heavyweight world champion last year when he failed a drugs test. Joshua instead fought Andy Ruiz Jr, losing in New York before avenging his defeat six months later in Saudi Arabia.
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