Chelsea manager Jose Mourinho has admitted his surprise that Cesc Fabregas decided to move to Stamford Bridge in the summer transfer window.

Fabregas has marked his return to the Premier League with four assists in his opening five league appearances during the Blues' unbeaten start this term.

But the 27-year-old's move to Chelsea shocked Mourinho, who was convinced the player would either join Arsenal or remain at Barcelona to become the long-term successor to Xavi at Barcelona.

Arsenal turned down the opportunity to re-sign Fabregas, while new Barca manager Luis Enrique allowed the player to depart after his opportunities had begun to dwindle following the arrival of Neymar and amid the continued influence of Lionel Messi.

"I thought he was going to stay at Barcelona," the Chelsea boss said.

"I was looking at him as the natural successor of players that were getting older, like Xavi. The surprise for me was not that he didn't go to Arsenal, but that he was leaving Barcelona.

"He's 27 and it's the perfect age. Physically, he's on a high, mentally, he's very stable, he has tactical education. Cesc's stats are fantastic, the number of assists, the qualities he brings.

"One of the reasons Cesc is so important is because he can play in any position," the Portuguese continued.

"Even in Barcelona, he was playing many times as a No.9. He sometimes played on the left wing too."

Fabregas himself admits he was left with no choice but to join Chelsea after making the decision to leave the Nou Camp, with Arsenal spurning the chance to sign their former captain.

"Changing clubs is part of the game and people must remember it was Arsenal who didn't take up the buy-back option for me," he said. "What am I going to do - retire? No way.

"I can understand some people at Arsenal are sad, some people are upset, some people are even angry. But I have to look after myself. I had to make a decision.

"I wanted to keep playing football, enjoying myself and my career and I felt that joining Chelsea was the best option for me. There would have been a reaction wherever I had gone."