The Blues were beaten by Bayer Leverkusen 2-1 in the Champions League last night after leading to make it three losses in their past five outings in all competitions but Cech feels that it is the players who are at fault and not the new boss.
"The manager is not on the pitch, we are on the pitch and we are making mistakes," Cech told the club's official website.
"He cannot do anything about individual mistakes while he is standing by the bench. So the players are to blame and we know it and we try to make things happen and change. It is not easy but we keep going.
"We have been talking recently about the same mistakes - concentration and little details when we don't go to clear the ball. I think we need to be much more aggressive in terms of defending and we get punished all the time."