The training deal sees the teenage forward contracted to the Brazilian club until the age of 19, as he aims to follow in his famous father’s footsteps by making a professional career.
Mendes had already been playing for the Cruzeiro youth team and has now been handed a pathway to the senior team.
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"Today, we signed the contract of Joao Mendes, who is a promising player with interesting characteristics and who, I believe, will soon be integrating with our professional team," Ribeiro told Cruzeiro's website.
Cruzeiro director Amarildo Ribeiro said: "He is a tall player with high technical quality. A player who can play both as a box player and as a second striker.
“He is a player who, even with his size, has speed and finishes very well."
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