The 34-year-old striker had tested positive for cocaine metabolite benzoylecgonine following a World Cup qualifier against Argentina in October 2017, leading to Federation Internationale de Football Association banning him for six months.
In October, Guerrero tested positive for benzoylecgonine - the main metabolite of cocaine, something he has said is the result of drinking coca tea.
In the latest twist to a long-running saga which has kept the Andean nation on tenterhooks, the Swiss Federal Tribunal acknowledged that it would be harsh for Guerrero to miss what is likely to be his only chance to play at the tournament.
The Cas had said earlier on Thursday that it would not intervene in Guerrero's legal campaign to play at the World Cup.
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On Wednesday, May 30, she shared a similar snapshot , writing, "Happy time positive vibes #happyness #positivevibes". The expectant Nielsen posted photos of herself lounging on Instagram and Twitter .
Switzerland's supreme court says it has granted an interim order to freeze Guerrero's 14-month ban for a positive doping test.
"This decision does justice, at least partially, and I'm grateful to the Swiss court", said Guerrero, who has not formally been cleared of doping and could yet serve the remainder of his ban. Check out a few tweets from jubilant Peruvians below.
The victory means the former Bayern Munich player is now set to be captain of Peru at its first World Cup appearance since 1982.
That suspension was then halved by Fifa's appeal committee but the World Anti-Doping Agency (Wada) appealed to Cas and, less than two weeks after his six-month ban ended in May, they extended it to 14 months.
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After a bystander tells the officer to refrain from throwing blows, Weinman yells out, "you're not allowed to beat me like that". The camera was reactivated during the struggle with the woman seen in the third video. "These guys were looking for something".
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 federal judge agreed with the CAS panel, which also accepted the player's arguments of not being significantly at fault for the positive test.
His Fifa-imposed ban of six months had expired that same day.
But instead of accepting the ruling, Guerrero appealed to CAS in a bid to clear his name.
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But a Downing Street source hit back: "The PM recognised the necessity of providing certainty for businesses". The prime minister has already ruled out remaining part of the EU customs union.
Peru have been drawn in Group C alongside France, Denmark and Australia and will be delighted with the news that they can welcome the 34-year-old Flamengo forward back into the fold.