Real Madrid have announced the signing of River Plate youngster Franco Mastantuono.
The 17-year-old has agreed a six-year contract with Los Blancos, and his move to the capital giants will become official in the middle of August, when he turns 18 years old.
"Real Madrid CF announces that Franco Mastantuono will be a player for our club for the next six seasons, from August 14, 2025, to June 30, 2031," read a statement on the club's official website.
"Mastantuono developed in River Plate's youth system between 2019 and 2024, and was part of the first team during the 2024-2025 season. In February 2024, he became the youngest scorer in River Plate's history, winning an Argentine Super Cup with him.
"At 17, he is also the youngest player to play an official match with the Argentine national team in its entire history."
Mastantuono joins Real Madrid on a six-year deal
The Argentine had a €45m (£38.5m) release clause in his River contract, with a number of clubs believed to be interested in signing him during this summer's transfer window, but Real Madrid have managed to get the deal done.
Paris Saint-Germain are believed to be one of the other teams that made an attempt to sign him.
Mastantuono will not represent Real Madrid during the Club World Cup, though, and will instead play in the competition for River, with his switch to Bernabeu becoming official in August when he turns 18.
Viewed as one of the best young talents in world football, Mastantuono has scored 10 times and registered seven assists in 61 appearances for his current side in all competitions.
Mastantuono could be an immediate starter at Real Madrid
Alonso allegedly believes that Mastantuono is a player capable of making an immediate impact at Bernabeu.
As a result, one of the attacking positions in the starting side could be handed to the Argentine, with ESPN claiming that glowing reports have been returned on his personality and attitude.
Real Madrid are said to be confident that the youngster has the mindset to deal with becoming a starter for the capital giants, and it will be fascinating to see how he performs for River at the Club World Cup.
Mastantuono has become Real Madrid's third signing of the summer after Dean Huijsen and Trent Alexander-Arnold, and more are expected as Alonso looks to build a squad capable of challenging on all fronts next season.