Real Madrid skipper and captain Iker Casillas is eager to push his team mates to their fullest potentials and to do better after their lackluster performance against Real Sociedad.

The European champions threw away a 2-0 lead to fall 4-2 at the Anoeta stadium on Sunday.

Casillas told the Spanish newspaper, Marca, that it was neither the journey nor the attitude they must have. "We were horrible," he said.

"We had a negative approach in every aspect of our game. We can't continue to play like this.

"I want to congratulate Real Sociedad because they played a sensational match."

Real looked to be heading for a comfortable win after goals from Sergio Ramos and Gareth Bale had put them ahead after 11 minutes played.

However, the home side hit back with four goals to stun the Spanish giants.

"To have gone up 2-0 after 11 minutes is unusual, more so when playing there," Casillas said. "But when you lead 2-0 you can't possibly throw that away in the manner we did."

Casillas is headstrong that Real must reach farther and train more intensively on their set-piece defending during the international break.

"We need to be more focused when dealing with these type of plays," the Spain international said. "We are all guilty, not just those that play at the back but everyone in the team.

"We need to make changes because it is not normal what happened against Real Sociedad."