Rafinha suffered a meniscus injury to his right knee in Barcelona's match against Granada, the club have confirmed.
The Brazilian was named in the starting line-up for the Liga clash at the Nuevo Los Carmenes, where Luis Enrique's title-holders were without the suspended Lionel Messi.
The absence of the Argentina star saw Rafinha, who also started the 4-2 victory at home to Valencia before the international break, deployed in a more advanced role.
But the 24-year-old had to be withdrawn after just 17 minutes, to be replaced by Paco Alcacer.
Alcacer went on to score in a 4-1 win for Barcelona, with Luis Suarez, a Matthieu Saunier own goal and Neymar's 100th strike for the club completing the scoring for Luis Enrique's men, who move within two points of La Liga leaders Real Madrid, as the beaten hosts finished the match with 10 men following Uche's sending off.