The 18-year-old enjoyed a fruitful start to the campaign before suffering a meniscus injury in November, and he has been sidelined ever since undergoing surgery for the first time.
However, Fati's comeback is taking longer than initially expected, and according to Marca, he will be operated on again this Thursday in order to finally heal the niggling issue.
The report adds that the teenager will be in the care of Dr. Jose Carlos Noronha, who has worked with the likes of Cristiano Ronaldo, Arjen Robben and Angel Di Maria, and he has a track record in helping players speed up their recoveries.
However, the chances of Fati recovering in time for the Euros or Olympics are thought to be extremely slim, so he will instead aim to be fit for the start of the 2021-22 La Liga season.
Fati chalked up five goals and four assists in 10 appearances across all competitions for Barcelona before his season-ending injury.
Monaco 
Stade Brestois 29 
Bordeaux 
Nimes 
Bayern Munich 
FC Augsburg 
Paris Saint Germain 
Toulouse 
CSKA Moscow 
FC Rostov 
Leicester 
Chelsea 
Valencia 
Betis 
Dynamo Kyiv 
Chornomorets Odesa 
Verona 
Inter 
Bayer Leverkusen 
FC Heidenheim 
Borussia Dortmund 
SC Freiburg 
VFL Wolfsburg 
Union Berlin 
Arsenal 
Nottingham Forest 
Everton 
Brentford 
Spartak Moscow 
Lokomotiv Moscow 
Rangers 
Dundee Utd 
Atletico Madrid 
Alaves 
Lens 
Marseille 
Ingulets Petrove 
Shakhtar Donetsk 
AC Milan 
Juventus 
ST Malo 
Manchester City 
Tottenham 
Eintracht Frankfurt 
Werder Bremen 
Girona 
Espanyol 
Feyenoord 
Heerenveen 
ST Etienne 
Montpellier 
Grenoble Foot 38 
Heart Of Midlothian 
Celtic 
Reims 
Lyon 
PSV 
Groningen