Wiltz has become the focus of the summer transfer market. His transfer fee is as high as 125 million euros, second only to Isaac (145 million euros) who transferred from Newcastle to Liverpool.

"He wanted to win the Champions League and we thought we could go further with this squad. He saw us winning the Bundesliga, but winning the Champions League in Leverkusen might be more difficult." Leverkusen CEO Fernando Carlo said in an interview with Sport1.

Carlo also revealed Real Madrid's chances of signing Wirtz in the summer: "If Alonso makes him an offer, he will definitely go to Madrid, but Alonso's influence at Real Madrid is not as good as with us."

He said that one of Alonso's strengths in Germany is "cooperating with our scouting department to determine which players should join our team."

In the end, Real Madrid did not introduce any players who could replace Wirtz's role. This summer, they signed full-backs Trent Alexander-Arnold and Alvaro Carreras, centre-backs Huizen and Mastantuono.