Madrid - Barcelona midfielder Cesc Fabregas could be out of action for up to four weeks after tearing a thigh muscle in Sunday's 2-1 win at Real Betis.
The former Arsenal star came off after just nine minutes of the match in Seville, a game which saw team-mate Lionel Messi score twice to set a new record of 86 goals in a calendar year.
"He'll be sidelined for three to four weeks. Therefore, he'll miss the team's last three games in 2012 - the two Liga matches against Atletico Madrid and Valladolid and the away leg of the Copa del Rey against Cordoba," said a Barcelona statement.
"He could also miss the first games of 2013, against Espanyol and the return leg of the Cup at the Camp Nou."
Captain Carles Puyol was taken off at half-time suffering with a problem in his right leg.