The definitive departure of Luka Modric not only marks the farewell of a true legend of Real Madrid, but also a major marketing move. With the Croatian leaving, the number 10 will be available next season, being the most desired jersey number by everyone. It seems it won't be without an owner for long, with it being clear who his successor will be: Kylian Mbappé.
Mbappé started with the 9 in Real Madrid, while in Paris he became "famous" for wearing the 7. This will change next season. The number the French forward has always liked the most is 10, with his dream since childhood being to wear it at Santiago Bernabéu. In the summer of his arrival, the rumors were significant, but Florentino's response was clear: "You'll wear it when Modric leaves".
Said and done, this is the immediate plan. With Modric leaving, Kylian Mbappé will be the new 10 of Real Madrid, fulfilling the dream he had since childhood. In a famous comic about his life, it was revealed that one of the gifts he asked for as a child was the club's jersey with this number and the name Kylian. Everything will be the same except for this last part, opting to continue wearing his last name.

This way, the plan is clear: Kylian Mbappé will take Modric's 10 next season... Leaving the 9 available and causing a major jersey number shuffle in Real Madrid.
Kylian Mbappé, Luka Modric's heir: jersey number shuffle in Real Madrid
Not only will the 10 be available (although for a short time), as there will be multiple departures in Real Madrid this summer. Looking ahead to next season, in addition to the 12 and 24, the 17 of Lucas Vázquez and the 18 of Vallejo will also be available.
Taking advantage of Kylian Mbappé changing to the 10, everything points to the new 9 being Endrick, having all the trust of Xabi Alonso. The uncertainty will lie with the new signings, with the choices of Arnold, Dean Huijsen, or Álvaro Carreras being hanging in the air.

In this regard, nothing would be decided as of today, with various cases open on Florentino's table. But the important thing is moving: Kylian Mbappé will take the 10 with Luka Modric's departure, and the 9 will be for Endrick.