American Olympic silver medallist Christian Coleman is under investigation over concerns he may have missed three drugs tests. Coleman allegedly had three possible failures under the '”whereabouts” system in the last year.
The 23 year old sprinter is understood to be contesting at least one of the cases.
The 'whereabouts' policy requires athletes to let officials know where they will be for one hour every day as well as details of overnight accommodation and training. If he is found guilty the sprinter would face an automatic one-year ban and would miss next month's World Championships in Doha, Qatar and the Olympic Games in Tokyo, Japan next year.
Coleman had grabbed the silver medal at the 2017 World Championships in London behind fellow American Justin Gatlin while world record holder Usain Bolt was third.