Real Madrid's Brazilian international midfielder Casemiro could miss up to a month after suffering a leg fracture, the European champions said on Thursday.

The 24-year-old was forced off 20 minutes into Sunday's 2-0 win over Espanyol following a strong challenge.

He has suffered a fracture of the fibula in his left leg, Madrid said in a statement.

Real did not specify how long he would be out but Spanish media have put the recovery time at three weeks to a month.

Casemiro joined Madrid from Sao Paulo in 2013 but spent the 2014/15 season on loan at Porto.

He will miss Brazil's next two World Cup qualifiers, against Bolivia on October 6 and away to Venezuela five days later.