Barcelona midfielder, Gavi will have surgery after tearing his anterior cruciate ligament on international duty with Spain.
Gavi, 19, left the pitch in tears on Sunday after landing awkwardly when jumping to control the ball.
Tests have confirmed a complete tear of his right ACL and an injury to the lateral meniscus.
It means Gavi is unlikely to feature again this season and puts his chances of playing at Euro 2024 in doubt.
The recovery time for an ACL rupture or tear can be eight to 10 months which means he could also miss the 2024 Paris Olympics.
Barcelona confirmed the “complete tear of the ACL” on Monday and said a further update would be provided in the coming days.
Gavi has played 111 games for the Catalan club, scoring seven goals and providing 12 assists while he has made 27 appearances for Spain, scoring five goals.
He helped Barca to win the league title and the Spanish Super Cup last season.
Spain boss Luis de la Fuente described Sunday’s 3-1 over Georgia in Valladolid as the “most bitter victory I have experienced in my life” because of Gavi’s injury after just 26 minutes.