JOSE Mourinho has a policy of 'one slip-up and you're out' at Chelsea, defender Gary Cahill has revealed.

The Blues boss has become known for his hard line on team selection since his return to Stamford Bridge as was shown on Saturday when he dropped David Luiz following a poor performance on Wednesday night.

He has also made very public his belief that double player-of-the-year Juan Mata cannot presently give Chelsea what they need in midfield.

Now Cahill, who has had more match time under Mourinho Mark Two than almost any of his team-mates, has revealed the manager's zero-tolerance policy on errors.

Asked if this was the hardest he had ever been worked by a coach, Cahill said: “Maybe. I think with the squad being so big, you feel if you slip up once you might not get an opportunity for a while.

“It keeps you on your game, no one is complacent by any means. I that is a good thing. If you don’t perform then you will be out.

“It’s never easy when you have got a squad of international players. Also obviously with the manager, if you slip up, you will be out of the side. It is as simple as that.

"He has his own reasons for things and there is great competition.”

Speaking of Mourinho, known as one of football's hardest task-masters, the England defender said: “He expects to win games; he expects to win every game.

“He expects certain things from players. That is the way he manages, I think it is great and I’m sure it will rub off on the other lads. I’ve really enjoyed it.”

After a fair start, Blues hit trouble with defeats against Everton and Basel. Cahill says Mourinho did not hide his disappointment.

“Obviously there is a style that he wants to play, that he demands from certain players in certain positions,” he said.

“And I think early on in the season he was getting that, last couple of games maybe not. He’s let us know and we work on it in training.”

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