Chelsea manager Jose Mourinho has told struggling Serbian midfielder Nemanja Matic to keep it simple and remain patient in order to break out of a poor run of form.

The box-to-box midfielder was a fundamental factor as Chelsea cruised to the Premier League title last season, but has struggled to replicate his strong showings this term.

He was dropped to the bench for the Southampton defeat earlier this month and was pulled off 28 minutes after coming on as a halftime substitute.

The Blues have also been in poor form this season, they sit 12th in the table after nine league games and are 10 points behind leaders Manchester City but did record a 2-0 home success over Aston Villa on Saturday.

"Confidence is fundamental. Matic lost an easy pass when he came on, on Saturday, and the first reaction he had was to show a disappointment," Mourinho told reporters ahead of the Champions League clash with Dynamo Kiev on Tuesday.

"When you are full of confidence you don't show disappointment. You make a mistake, you know that you're not going to make another mistake after. So (stay) calm, let's go step by step.

"When you are a little bit fragile, simple. Make it simple. Think quick, make the right decision. Take the ball out of the pressure zone. Don't be worried about making a beautiful pass.

"Make just sure that you don't lose the ball, because if you lose the ball, you lose confidence. So, you know, step by step, step by step," the former Real Madrid manager added.

Mourinho was coy when asked about Chelsea's chances of picking up a trophy this season.

"We can win all four, we can lose all four. I think it is (possible), but I think it's also possible to lose all four. We are in October. Everything is open. We can win all four, we can lose all four," the 52-year-old Portuguese said.