Jose Mourinho believes Chelsea fans will be seeing a more mature player after Nemanja Matic completed his return to the club from Benfica this afternoon.

The Blues confirmed they had struck a deal for the Serbian midfielder this evening and the 25-year-old has signed a five-and-a-half-year contract.

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He will be available for selection for his second debut on Sunday against Manchester United, having previously joined the club from MSK Kosice in 2009.

Mourinho said of the new signing: ”I am very pleased that Nemanja is returning to Chelsea. He has grown as a player in Portugal and has become a fantastic all-round midfielder. I am sure he will become a very important member of the squad and help us to achieve our ambitions.”

Chelsea manager Jose Mourinho

Matic made three substitute appearances for the Blues in the 2009-10 season and departed in January 2011 as part of the deal which brought David Luiz, one of the most coveted players in Europe, from Benfica to London.

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He said: ”I am very happy for this opportunity to be back at this club. I feel very good because of that and just want to say I will give my best to help the team and make the Chelsea fans happy.”

Matic played in all but one of Benfica's matches as they progressed to last season's Europa League final, where they were eventually beaten by Chelsea in Amsterdam.

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