Oscar's taken Juan Mata's place, says Jose Mourinho

Juan Mata's status at Chelsea appears increasingly fragile after manager Jose Mourinho declared that Brazilian Oscar was now his number one playmaker.

Spanish midfielder Mata was voted Chelsea's player of the season in his first two campaigns at Stamford Bridge but he has lost his place in the side since Mourinho returned from Real Madrid during the close season.

The 25-year-old has made only three appearances so far this season, for a total playing time of 145 minutes, and Mourinho says he must adapt if he wants to force his way back into the team.

"It's part of a process with him," Mourinho said.

"One thing is to play with Ramires and Oscar in the side, them closing (down) each side, and Mata as a number 10 behind a striker, to have clever assists and to have clever passes; fantastic actions because he has great talent.

"Another thing is to adapt to the way we want to play. In this moment, Oscar is my number 10 and, if somebody tells me that Oscar is not Chelsea's best player since the beginning of the season, I'd have to disagree.

"I want to build with Oscar as my number 10. I want the other two players, from the sides, to adapt to that reality and to learn how to do things that they were not ready to do before."

Mourinho refused to elaborate on his reasons for omitting Mata but suggested he was dissatisfied with his displays in last weekend's 1-0 defeat at Everton and the shock 2-1 loss at home to Basel in the Champions League on Wednesday.

"There are things I cannot speak with you about," said the Chelsea coach, whose side have gone four games without victory.

"But he played against Everton from the beginning and you can analyse his performance.

"And he played against Basel -- not like (Demba) Ba or (John Obi) Mikel, coming in to rescue the game, but he came on when the team was winning 1-0 and when he had specific tasks to do."

Mourinho was speaking ahead of the west London derby against Fulham later on Saturday.