Defender Alex will join PSV Eindhoven from on a five-year contract from the end of the season, the club have confirmed.
PSV’s acquisition of 21-year-old Alex comes in the wake of their sale of forward Arjen Robben to Chelsea for £12m.
Media reports suggest the deal for Alex is worth €6-8m to the selling club Santos.
“Alex is known as a strong and modern full back,” said Frank Arnesen, who is in charge of scouting and transfers for the club.
“He has proved his skills so far on several levels. He played 80 matches for his team Santos and also matches for the Copa Libertadores and Brazilian national youth teams.”