Real Madrid boss Carlo Ancelotti insisted that his star-laden side needs to find a balance between attack and defence as they were again humbled by local rivals Atletico Madrid 2-1 at the Santiago Bernabeu on Saturday.
Atletico have yet to be beaten by Real in three meetings already this campaign after suffering a heartbreaking Champions League final defeat to Los Blancos back in May as they also won the Spanish Super Cup last month 2-1 on aggregate.
A second consecutive La Liga defeat for Real leaves Ancelotti's men six points adrift of Barcelona and four behind Atletico after just three games of the new league season.
And the Italian was at a loss to explain how his side petered out in the second period after a promising opening 45 minutes, just as they did in losing 4-2 to Real Sociedad a fortnight ago.
"The first-half was good like at Anoeta and the second-half wasn't," said Ancelotti.
"We played with intensity and aggression in the first-half which is what you have to do to beat Atletico, but we didn't do that in the second-half."
Real's deficiencies from set-pieces were once again laid bare after just 10 minutes as Tiago headed home Koke's corner.
However, the hosts responded through Cristiano Ronaldo's equaliser from the penalty spot and were only denied a half-time lead by some superb goalkeeping from Miguel Angel Moya.
It was a different story after the break, though, as Atletico grew into the game after the introduction of Arda Turan and Antoine Griezmann and won it 13 minutes from time when Turan swept the ball into the far corner from the edge of the box.
"I think the mistake for the first goal cost us the game because we used so much energy to level we paid for it in the second-half," added Ancelotti.
However, he insisted it is not his favoured 4-3-3 system that was to blame for the defeat.
"We don't have a problem with this system. We know the system very well, we had a problem with intensity in the second-half today in the way we had a problem with attitude at Anoeta.
"I have a lot of experience. This isn't the problem. As I have said many times, too many times, we need a balance with quality players."
Atletico boss Diego Simeone, meanwhile, said his side's victory was a massive morale boast for a squad that has been overhauled after their La Liga winning campaign last season.
"I think it is the first time we have won twice in a row in the league at the Bernabeu and that is very important for our fans and a new group of players," said Simeone, who watched the game from the stands as he continues to serve an eight-game touchline ban.
"We still have difficulties ahead to have the consistency we want, but with the work rate they showed and the play they showed in the second-half I am happy."
Despite his side once again proving they can beat the biggest sides in the world even on the road, though, Simeone insisted the victory hadn't changed his opinion that another title challenge will be beyond Atletico.
"The greatest thing about football is that it always gives you a chance and I think we have taken advantage of that, but today's result doesn't change the discourse.
"There were 10 or 11 players that left, but we have a nucleus that is the strength of our group and hopefully the new players will continue to grow.
"The strength of our game remains our work ethic."