The Athletic reports that Borussia Dortmund, who are seeking defensive reinforcements, have shown interest in Joan Martínez, who is from the Real Madrid academy. Sources close to the club suggest the 18-year-old is being considered. It is also reported that Dortmund are not the only top club observing the central defender. The player signed a new contract with Real Madrid in September. The contract is said to extend until 2029 and reportedly includes a release clause of 70 million euros. It is thought that Borussia Dortmund are considering a loan move for Martínez, who has not made his first-team debut under coach Xabi Alonso. It is expected that the player will consider a temporary transfer if his opportunities at Real Madrid remain limited.