Peru captain Paolo Guerrero is testifying at the Court of Arbitration for Sport (Cas) in a doping case that could see him miss his country’s first World Cup appearance for 36 years.

Guerrero was met by around 20 Peru fans outside sport’s highest court in Lausanne, Switzerland, before an appeal hearing on Thursday into his positive test for cocaine metabolites at a World Cup qualifying game last October.

CAS said a verdict on the striker’s case could come next week.

Peru must name a provisional squad by May 14th for its first World Cup appearance since 1982. They are scheduled to play three friendlies against Scotland, Sweden and Saudi Arabia, before kicking off their World Cup campaign in Russia against Denmark in Group D on June 16th.

The World Anti-Doping Agency (Wada) has appealed to increase 34-year-old’s ban from one to two years after disagreeing with FIFA’s original punishment.

Guerrero, who plays for Brazilian side Flamengo, separately appealed to Cas to overturn the six-month ban imposed by Fifa, which expires this week. His lawyers have argued the small amount detected was not performance enhancing and was accidentally consumed in contaminated tea.

Fifa initially suspended Guerrero for one year, which would have kept the Peruvian out of action until 3rd November, but the sanction was reduced on appeal, clearing him to play at the World Cup.

Anti-doping rules prohibit the use of cocaine in an athlete's competition period.

Guerrero tested positive at a qualifier against Argentina which Peru drew 0-0.