Barcelona goalkeeper Victor Valdes has paid tribute to 'impressive' Real Madrid counterpart Iker Casillas ahead of the arch-rivals' clash this weekend.
The duo, who were both part of the Spain squad that lifted the World Cup last summer, will be pitted against each other in the Primera Liga at the Bernabeu on Saturday.
Valdes was the third-choice keeper behind No.1 and captain Casillas in South Africa, while Liverpool's Pepe Reina took the number two spot.
Despite Casillas being a key performer for Barca's fierce rivals, Valdes admits he respects the 29-year-old Real veteran.
He told Spanish newspaper El Pais: "What a keeper! It is one thing to have him in front of you and another to see him on the television.
"You already have the intuition that he is really good.
"I had never had the opportunity to work with him before and it was during the (World Cup) training sessions that you really see the capabilities of a footballer.
"Iker is impressive. The power he has. The confidence."
Defending La Liga champions Barcelona are top of the league table and eight points ahead of nearest rivals Real with seven matches left to play going into Saturday's showdown.
The match could be the first of four meetings between the two sides in less than a month, with a Copa del Rey final looming on April 20th and the strong possibility of the two sides clashing again in the UEFA Champions League semi-finals at the end of April and beginning of May.