As the legal battle for Paolo Guerrero to be eligible at this year's World Cup continues, Peruvian Football Federation president Edwin Oviedo has delivered a sworn statement to the Swiss Federal Tribunal.

Guerrero had just completed a six-month ban from FIFA after testing positive to a byproduct of cocaine consumption, but the Court of Arbitration for Sport extended his ban, ruling him out of the World Cup.

The 34-year-old attacker lodged his appeal to Switzerland's highest court on Friday, with the head of Peruvian football's governing body providing written support, as confirmed by an official FPF communication.

"Paolo Guerrero, as the leader, has a high level of confidence that radiates to the whole of the team," Oviedo's statement read.

"He is the unquestioned captain of the Peruvian team and an emblem of hope for the entire nation.

"I beg with all my heart to take into account not just Paolo's interests, but the entire nation's."

Oviedo is also in Switzerland currently, asserting it is where he "belongs" as the lead representative on Peruvian football on an administrative level.

Guerrero has maintained that benzylecgonine, a metabolite of cocaine, was found in his system because of a herbal tea drink contaminated with coca leaf, an ingredient used as a non-narcotic remedy in South America.

The world players' union, FIFPro, and the captains of Australia, France and Denmark – Peru's group opponents in Russia – have also appealed to FIFA to lift the ban, highlighting CAS' recognition Guerrero ingested the substance unknowingly and did not seek to gain an athletic advantage.