World footballers' union FIFPro has contacted FIFA over a drugs ban handed to Paolo Guerrero that could see the Peru captain miss the World Cup.
Guerrero tested positive for cocaine metabolite benzoylecgonine after Peru's World Cup qualifier against Argentina in October 2017.
The Court of Arbitration for Sport then upheld an appeal from the World Anti-Doping Agency to extend Guerrero's suspension to 14 months.
Guerrero is set to miss the World Cup as a result, an outcome FIFPro previously described as "unfair and disproportionate".
And the organisation has now contacted FIFA in a bid to have Guerrero's ban overturned, so he can go to the World Cup with Peru.
"We are hoping for a breakthrough in the next 24-48 hours," FIFPro said in a brief statement posted on social media on Sunday.
Guerrero, 34, had an initial one-year ban reduced to six months by FIFA.
He returned to action for Brazilian club Flamengo before being named in his country's provisional squad for their first appearance at a World Cup since 1982.
FIFPro has argued football needs to consider doping reforms as the body believes the ban given to the Peru captain "defies common sense".
