Peru coach Ricardo Gareca said Paolo Guerrero is ready for the World Cup after the striker was cleared to play in the tournament despite a doping ban.
Switzerland's supreme court granted an interim order last month that froze a 14-month ban after he tested positive for cocaine metabolites following a World Cup qualifier against Argentina in October.
The captains of Peru's Group C opponents -- France, Denmark and Australia -- wrote to FIFA earlier this year to express support for lifting Guerrero's ban, and Gareca said the team wanted to "express our gratitude" to them for the gesture.
"It was a great demonstration of solidarity with our national team, and this has been very positive for Guerrero," Gareca said at a news conference in Saransk, Russia, on Friday.
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Guerrero, 34, is Peru's all-time leading scorer, and the former Bayern Munich and Hamburg striker, now playing for Flamengo, could have missed his only chance to appear in the World Cup.
"It was an important example of support and solidarity by all captains," Peru defender Alberto Rodriguez said. "Having him here -- of course, it's great and important."
FIFA didn't immediately challenge the ruling because Peru's opponents made their support for Guerrero clear.
Guerrero has proclaimed his innocence all along. He has said he failed his drug test because he drank tea from a cup tainted with coca leaf residue in a Lima hotel.
Now the biggest questions surrounding him seem to be how mentally and physically fit he will be after a long, emotional legal struggle to be allowed to play -- not to mention how he will handle the pressure of being the most accomplished member of a passionately followed national side playing in the World Cup for the first time in 36 years.
"Paolo is playing very well since playing with the national team," Gareca said. "I know he's very, very happy and I think he's very well situated."
Guerrero scored five goals in World Cup qualifying and twice in Peru's last friendly -- but that was against Saudi Arabia, who yielded five goals against Russia on Thursday.
Gareca called Guerrero "very, very fit," and said he "really is ready to play," but did not say whether he would against Denmark in the teams' opener on Saturday.
"I always wait until the last second to decide," Gareca said. "It's difficult to decide."