Mata has endured a marathon 12 months of football that has seen him play an entire season with Chelsea, and feature for Spain at Euro 2012, London 2012 and the Confederations Cup earlier this summer.
Mata said: "I've had a long two years? I've had a long five or six years! I can't remember the last time I had four weeks off. It was needed. When you have a season where you played more than 60 games - you have to rest for a month.
"Every manager is different and has his own kind of work. But in terms of intensity, the training sessions are so high under the new manager. And the plan is to put that level of intensity into the games as well to make us competitive."
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