Mexico defender Diego Reyes has signed a five-year contract with Porto and will move to the Estadio do Dragao for an undisclosed fee in the summer.
A statement on Porto's official website read: "Diego Reyes, 20, will be a Porto player. The young Mexican has signed a contract until 2018 and will join the Dragons for the start of next season.
"Reyes is one of the most promising centre-backs in the world, despite his youth. In the summer he became an Olympic champion with Mexico and attracted the interest of several leading European clubs."