American boxer Claressa Shields, the undisputed world champion in three weight classes, has been suspended and is under investigation after testing positive for marijuana following her victory over heavyweight Danielle Perkins in Michigan.

The Michigan Unarmed Combat Commission suspended Claressa Shields after an “oral fluid sample” showed the presence of marijuana.

Ms Claressa Shields conduct as a licensed professional boxer constitutes an imminent threat to the integrity of professional boxing, the public interest, and the welfare and safety of professional athletes;