The 19 year-old has agreed a four-and-a-half-year contract at the Amsterdam ArenA and will link up with his new team-mates at the end of Brazil's South American Under-20 Championship campaign in Ecuador next month.

The teenager only made his senior debut in October, going on to score three goals in eight Campeonato Brasileiro appearances for Sao Paulo.

Ajax will pay the Brazilian side $17.1 million up front, with a further $4.3 million potentially payable in bonuses.

The Amsterdammers' technical director Marc Overmars said: "Neres is a player we have wanted for a while. He is one of the biggest talents in South America and it's nice that he's chosen Ajax.

"He is a right-winger who can play on the left, which is what we need. He's only 19 and he will have to get used to it here.

"We have a lot of important games ahead, so I am happy that he is coming here now and not just in the summer."

The news will be a boost for Ajax supporters, having seen Anwar El Ghazi depart for Lille and Mitchell Dijks join Norwich City earlier on Wednesday, though the latter was only a temporary deal.