Petr Cech rolled his shoulders, turned his head sharply from left to right and took in the wide dimensions of the pitch at Camp Nou. Awaiting the whistle for kick-off, he ran through his psychological exercises.

“It is hard to describe,” he says, “but I talk to myself. I imagine there is a point where a guy has the ball at his feet and then I look, for example, to what is happening on the left. Then I say to myself, ‘Have a look there, have a look here, look what is around’. In this game, you need to see everything.

“I say to myself, ‘There are not just two players you need to be watching, with Barcelona you need to be watching 10. You have to always follow everyone’.”

If there were voices in Cech’s head during the game in Catalonia on Tuesday, they talked sense. He had a sound night with his hands and his reflexes for Chelsea. No goalkeeper had kept a clean sheet at Barcelona’s stadium in a competitive match since Edwin van der Sar 53 weeks earlier. And for a keeper who had conceded four goals in his previous outing in the Champions League, the shut-out was more than welcome.

Cech has survived his period of stiffest scrutiny in four and a half years as a Chelsea footballer. “The criticism was right, for two games,” he says, “but when you play 55 games in a season and have two bad games [against Liverpool in Europe and Bolton in the Premier League], that can happen to anyone. It was the first time in my Chelsea career that I have made mistakes in successive games. I made a mistake for the Bolton goal and then straight away for the Liverpool goal.

“You know, it was not a nice period. Sometimes it is really hard. You see your mistake and you don’t recognise yourself. You say, ‘Oh my God, how can you do that?’ This can be a good example though, to yourself, to see yourself in a bad position. Then you have to say, ‘I have to be more careful in the future’.”

Cech feels the dip in form and confidence has passed. “We had a look at those games, we knew — me and the goalkeeping coach — what was wrong. It was just about finding a way not to repeat it. The biggest mistake is when you start changing things because of one mistake. I didn’t change anything in my routines, didn’t alter training.

“The boss [Guus Hiddink] and I spoke briefly and he asked me if I felt well, if there was a problem. I said, ‘No, boss’. It was just a matter of saying, ‘Okay, I don’t feel any problem with continuing after two bad games’. That decision is the manager’s but usually you don’t change the goalkeeper in a first bad period.”