"Mr Guerrero submitted an urgent request for the suspension of the execution of that sanction in order to participate in the next FIFA World Cup in Russian Federation". Guerrero is the top of player that can earn you points with a moment of magic and greatly boosts the team's chances of making some noise this summer.
In a statement, FIFPro said they were "delighted" by the outcome but expressed regret that the Flamengo striker must face proceedings after the finals.
The interim ruling puts the ban imposed by the court of arbitration for sport on hold until full consideration of the case at a later date.
However, on Thursday, the Swiss Federal Tribunal agreed to temporarily lift the doping suspension while it considers his appeal against the ban, freeing him to play for Peru at their first World Cup finals for 36 years.More news: Xiaomi unveils Mi 8 phones, its '8th anniversary flagship'
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The verdict came four days ahead of Fifa's deadline for Peru to finalize its 23-man World Cup squad.
The case has attracted widespread attention in the build-up to the tournament, with Guerrero claiming he ingested the banned substance after drinking an aromatic tea made from coca leaves.
The ban, backdated to November, was reduced to six months less than two weeks later after the player protested to FIFA's Appeal Committee, meaning he was eligible for the World Cup which starts next month. The panel decided a ban to January 2019 was an "appropriate sanction ... in light of Mr Guerrero's degree of fault". That included a letter signed by captains of Peru's three World Cup opponents - France, Denmark and Australia - urging he be allowed to play.
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.