According to reports, Mastantuono will receive a salary of €3.5 million per year, which is similar to that of another young player, Endrick, who earns €4.1 million annually.
Mastantuono had a productive season at River Plate, playing 22 matches and scoring seven goals, while also providing four assists.
As a first-team prospect, Mastantuono is expected to make a significant impact under coach Xabi Alonso in the upcoming season.
