Estupinan's move to Milan comes as the club looks to rebuild after a disappointing Serie A finish last season. Milan missed out on European qualification, their worst finish in a decade.

The club has been working to strengthen its squad under the leadership of former manager Massimiliano Allegri, who returned to Milan in May. They have also signed former Real Madrid midfielder Luka Modric in recent weeks.

Estupinan, 27, made 104 appearances for Brighton since joining the Premier League club from Villarreal in 2022. Brighton's manager, Fabian Hurzeler, praised Estupinan's contributions to the team.

"Pervis has been a valuable player for us, and we appreciate his commitment to the club," Hurzeler said. "He's at a stage in his career where he's looking for a new challenge, and we wish him the best for the future in Serie A."