Suárez Castrelo will join Real Madrid as a free agent after his contract with Atletico expired.
He was a highly promising young player within the Atletico youth team, but chose not to extend his contract with the club.
As a result, Suárez Castrelo has not played for Atletico since December.
Additionally, Real Madrid has also signed two other young players: Ares Capetana, a defender from Leganes U16s, and Leon Westin, a 16-year-old Swedish midfielder from Las Palmas.