Barcelona forward Ansu Fati will be sidelined for four months after undergoing knee surgery, the La Liga club said on Monday.
Fati, who turned 18 last month, ruptured the internal meniscus in his left knee during Barcelona's 5-2 home win over Real Betis on Saturday.
"Ansu Fati has been operated on successfully by Dr. Ramon Cugat... under the supervision of the Club's medical staff," Barcelona said in a statement. "The player will be out for approximately four months."
Fati will miss Barca's crunch Liga trip to Atletico Madrid later this month, the remainder of the Champions League group stages and the Spanish Super Cup, set to be held in January in Saudi Arabia.
Fati has been one of Barca's standout performers this season, scoring five goals in 10 appearances in La Liga and the Champions League.
Last season he became the club's youngest ever league goalscorer and the youngest scorer in the history of the Champions League.
RB Salzburg hit by COVID-19 outbreak ahead of international break
RB Salzburg will not release players for international duty after six players tested positive for COVID-19, the Austrian champions said on Monday.
The entire squad had returned negative results for COVID-19 tests last Friday but another round of tests for international players on Sunday revealed six positive cases.
The group of infected players, who are all asymptomatic, have been placed in isolation.
"The rest of our squad have begun a team quarantine according to the prevention concept," Salzburg said in a statement.
"This means that they can only travel between their house, the training ground and match locations.
"All international call-ups for FC Red Bull Salzburg players have also been rejected for now."
The squad will undergo another round of COVID-19 testing later on Monday.