Lionel Messi lasted just 10 minutes of Barcelona's home game with Las Palmas on Saturday before being substituted with a knee problem.
The Argentina international sustained the injury when visiting defender Pedro Bigas put in a last-ditch challenge to block a shot.
Messi left the pitch to undergo treatment and initially seemed to be ready to continue after rejoining the action but he sat down once more minutes later and was unable to carry on.
Youngster Munir replaced Messi and joined Luis Suarez and Neymar in Barca's three-pronged attack.
The four-time Ballon d’Or winner’s injury could see him miss the upcoming Champions League match versus Bayer Leverkusen, against whom Messi scored five times the last time they met in March 2012.
Messi has been a key figure for Barcelona this term, scoring six goals in nine appearances in all competitions ahead of Saturday’s meeting.
