Carlo Ancelotti pondered on Real Madrid's poorest performance since his return to the club, a 2-1 loss to Espanyol.
Los Blancos' dismal week got even worse when they squandered a chance to reclaim a three-point advantage at the top of LaLiga on Sunday at RCDE Stadium.
Madrid were sensationally defeated 2-1 by Moldovan club Sheriff in the Champions League in midweek, with goals from Raul de Tomas and Aleix Vidal deciding the game.
Although Karim Benzema brought one back, Ancelotti was unflinching in his assessment after seeing his team slip up before the international break.
The Italian said: "It was our worst game [of the season]. We played badly, there is not much more to say. We have to change our attitude this week.
"The defeat is not an accident because we deserved to lose. We are worried because two defeats in a row at this club is not customary and we must remedy this, correcting the errors."
During the international break, Ancelotti believes Madrid should focus on their faults.
He added: "We have started with an idea and the idea has changed with the first goal conceded. We were not able to keep calm and the idea and the team has been poorly positioned with the ball and without it.
"The approach was quite clear, I am not going to explain it now. The team has been very messy, with and without the ball. We have to fix it, I have discussed it with the players and they agree.
"Now comes the break. Sometimes it is better to play again immediately, but you have to use the break to reflect."