The Polish striker will miss games against Espanyol, Atletico Madrid and Getafe when LaLiga resumes after the World Cup.
Sami Khedira spent the night under observation in hospital after suffering a concussion in Tuesday's King's Cup game.
IMAGES from football matches played across leagues in Europe on Sunday.
Cristiano Ronaldo scored on his return from injury as Real Madrid thrashed Osasuna 5-2 at the Santiago Bernabeu on Saturday to equal the club's 1960-61 record of 15 successive La Liga wins.
Real Madrid did not specify if he would be out of action for any length of time
Substitute Sergio Araujo struck a late equaliser as Las Palmas held Real Madrid to a 2-2 draw and left them with a one-point lead over Barcelona at the top of La Liga on Saturday.
Promoted Alaves dealt champions Barcelona a shock 2-1 defeat at the Nou Camp on Saturday while Cristiano Ronaldo returned from injury to help Real Madrid thrash Osasuna 5-2 and go two points clear at the top of La Liga. With Lionel Messi, Luis Suarez and Andres Iniesta on the bench, Barcelona went behind to the visitors in the 39th minute before Frenchman Jeremy Mathieu equalised in the 46th. Ibai Gomez then scored the winner in the 64th.