Atletico Madrid signed striker Julian Alvarez from Manchester City Monday in a deal reported to be worth up to 85m euros ($93m).
"The club has reached an agreement with City for the transfer of the Argentine forward, who has signed a contract for the next six seasons," said Atletico in a statement.
Spanish reports say Atletico will pay 75m euros for the forward, with potentially 10m more in bonuses.
The 24-year old Alvarez arrived at City for just £14m (16m euros) in January 2022 from River Plate, winning two Premier League trophies and the Champions League among other silverware.
Alvarez also helped Argentina lift the World Cup trophy in December 2022 and the Copa America in 2021 and 2024.
"I say goodbye to this amazing club, with a lot of emotion," Alvarez told City's club website.
"These have been two very special years. During this time, I have grown and learnt a lot - both as a player and as a person."
Alvarez scored 36 goals for City in 103 appearances across all competitions.
"He's incredibly loved by the team for his behavior but like I said many times for many players, he wants to leave and have a new challenge," said City coach Pep Guardiola last week.
Diego Simeone's Atletico have also signed Robin Le Normand and Alexander Sorloth as they reinforce heavily to compete with Real Madrid and Barcelona, following a disappointing fourth-place LaLiga finish last season.
Atletico begin the new campaign with a visit to face Villarreal on August 19.
