The experienced goalkeeper believes the Spanish champions have plenty of alternatives for their injured players, and is not too worried about the recent criticism aimed at him
The reigning champions will have to make do without the services of Fabio Coentrao, Alvaro Arbeloa and Marcelo after the trio picked up injuries while away on international duty, but the 31-year-old has insisted that they have adequate replacements.
"We have enough alternatives to plug the gaps left by the Fifa virus. There are players in our reserves who are very capable indeed," Casillas told reporters at a promotional event.
"I am sure the boss will pick the best people for the game against Celta."
Casillas also took the time to discuss the criticism he has recently received, and insisted it is a part of the game to which he has become accustomed.
"You take the criticism with a sense of humour. You have to respect people’s right to criticise. As long as it’s constructive criticism, it’s a positive thing.
"When you’ve been at the top and in a club like Real Madrid this long you know that in two or three matches things can change. I’ve been living many years with this."
Saturday's match at the Santiago Bernabeu kicks off at 18:00CET.