Wednesday night's game was not without controversy, with Didier Drogba convinced he should have been given a penalty when the score was still 1-1.
But Cech said: "There are no excuses.
"We need to look first at ourselves and then we can criticise the other people because we put ourselves in the situation where we were 1-0 up and we could have killed the game off.
"Then there would be no discussion whatsoever about things that were happening in the game.
"We have to take it like that and make sure that this is the last time it happens."