Real Madrid coach Carlo Ancelotti says they're wary facing Real Sociedad on Sunday.
Ancelotti recognises the current impressive form of La Real.
"Real [Sociedad] are playing very well and have a good dynamic," he said in a press conference.
"We have to improve in the first half. After what happened against Atleti, it's important to play a complete game offensively and defensively."
Then he gave his reflections on the Copa del Rey quarter final against Atletico Madrid that took place on Thursday.
"It was a competitive, even match," he said. "I think we deserved to win on our side. The rest is something I'm not going to talk about.
"The only system I know is the one I will use tomorrow."