The 24-year-old has played more than 50 times for the Blues, including in their Champions League final victory over Bayern Munich in 2012.
"The way he plays the game and as a person, too, he'll fit in here great and it will be good for him also to be playing games. He has real enthusiasm for the game and he's looking forward to playing here.
"We're grateful to Chelsea for allowing him to come here on loan and we know he'll be really good to work with."
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