According to Mundo Deportivo.
Real Madrid soccer team
16 year old center back
Joan Martinez
The player has shown remarkable potential and maturity after a standout performance in training ahead of the new season. The Spanish native has attracted a lot of attention from the team with his performances in training.
Joan Martinez came on as a second half substitute for Rüdiger in Real Madrid's warm-up match against AC Milan. Despite being only 16 years old, Martinez was very solid in the center back position. He had a 93% pass success rate, lost possession only twice, and created a scoring chance from a corner kick in an outstanding performance.
Real Madrid originally planned to bring in a new center back, Yoro, but the transfer was unsuccessful. In this case, Real Madrid is not rushing the transfer market to find a new center back, but is looking to tap the potential internally. Joan Martinez is expected to be the team's future focus and subsequently one of Real Madrid's center back options.