Former Real Madrid coach Fabio Capello says Carlo Ancelotti cannot maintain his goalkeeper rotation policy.
For now, Iker Casillas is playing in the Champions League, while Diego Lopez is holding his place in the La Liga.
"It is difficult to understand why one is playing in Champions and the other in La Liga. You can't change the keeper as often as you can a midfielder, it is a specialised position," said Russia boss Capello.
"Both are great goalkeepers. When I had them, I also had problems deciding between the two, but Iker should not have any problems in going to the World Cup."