Real Madrid blew a 2-0 lead to lose 4-2 at Real Sociedad yesterday.
Madrid had looked set to sweep Sociedad aside as they struck twice early on through Sergio Ramos and Gareth Bale while also hitting the woodwork through the Spain defender.
The visitors also had a number of other chances to increase their lead before Sociedad staged a stunning comeback that saw them snatch the victory through goals from Inigo Martinez (36), David Zurutuza (41 and 65) and Carlos Vela (76).
That earned Sociedad their first points of the new season and came at the end of a week which saw them beaten by top-flight newcomers Eibar last weekend and knocked out of the Europa League on Thursday by Krasnodar.
Real coach Carlo Ancelotti said: "It is not easy to evaluate this match. There were two matches. The first 30 minutes were very good, with quality, pace and focus. The rest was very bad. It is difficult to explain what happened. We conceded corners, free-kicks We're very sorry, I don't like the team to play like that for an hour. The first half an hour was very good, but we have to think and change this.
"It is a defeat that I don't like at all. Sometimes you can have a bad match but a team like Real Madrid, when they are winning 2-0, have to keep concentrating and maintain their attitude to win the match. We didn't do that, I am responsible and we'll do something to change."
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