Barcelona manager, Ronald Koeman, could be without Lionel Messi for three games in October, including the El Clasico against Real Madrid, if he travels for international duty.
Argentina's 2022 World Cup have matches against Ecuador on October 8 and Bolivia on October 13.
FIFA has confirmed that players situated in Europe will be available for CONMEBOL qualifiers, but a number of clubs have raised concerns.
Under the current regulations in Spain, anyone returning from South America is required to quarantine for 14 days.
This means Messi will not be able to feature in LaLiga matches during that period.
The 33-year-old would miss matches against Getafe and Alaves and crucially the big fixture against fierce rivals Real Madrid.