However, the nation were left outraged after their inspirational captain received a 14-month ban from CAS, after being tested positive for cocaine metabolite benzoylecgonine, which was allegedly attained from coca tea, a common drink in South America.
However, the World Anti-Doping Agency (WADA) launched a successful bid to extend his suspension to 14 months, meaning that he had been expected to miss the competition in Russian Federation.
The tribunal, Switzerland's highest court, effectively "suspended" the CAS ban and said: "Guerrero can now participate at the next World Cup". The appeal is directed against the CAS decision partially-upholding the appeal filed by the World Anti-Doping Agency (WADA) against the decision issued by the FIFA Appeal Committee on 20 December 2017 and incresing Mr Guerrero's suspension from 6 to 14 months.
The TFS has upheld this request, allowing the Flamengo player to feature in Russian Federation.
The former Bayern Munich player is now set to captain of Peru in its first World Cup appearance since 1982.
"While Guerrero has won a temporary reprieve from the Swiss federal court, it is unfortunate that he has to endure such a protracted legal wrangle that is still not over".
Domingo nublado y con temperatura agradable: Hay probabilidad de lloviznas
A la mañana estará inestable y a la tarde noche se espera por tiempo inestable con probables precipitaciones. Así lo indica el Servicio Meteorológico Nacional.
"Paolo Guerrero can take part in the next World Cup, the court said, according to The Guardian".
The federal judge agreed with the CAS panel, which also accepted the player's arguments of not being significantly at fault for the positive test.
That effectively ruled him out of action until January 2019, and Guerrero was suspended by his Brazilian club, Flamengo.
Earlier on Thursday (Friday NZT), CAS - which based less than a kilometre from the federal court in Lausanne - issued a statement saying it would not object if Guerrero was cleared to play in Russian Federation.
Guerrero made a heartfelt appeal to Federation Internationale de Football Association and its chief Gianni Infantino, which was powerless against the usually unchallenged arbitration of the CAS.
At the World Cup, Peru opens against Denmark on June 16 in Saransk.