Yes he does need to prove to Jose he can do it. Jose wants a certain make up from a player, that being one that works back, works incredibly hard and also operates at both ends of the field in a way he wants. This isn't Juan Mata FC, it's Chelsea FC with one of the greatest managers around in charge and people are questioning Jose and saying things like "He's clueless" etc, please listen to what Jose is saying when he address's questions about Juan Mata, it really isn't difficult. Oscar right now is nigh on the perfect player, he operates up and down the field, tracking back, going forward, creating chances and scoring goals, that's a perfect player for me and it looks like Jose agrees. In all this I am not saying Mata is shite as most of you will probably jump on the band wagon and say, just look at my profile etc I love the bloke, but let's look at the big picture, firstly what Jose wants and secondly at what Mata is up against in terms of Oscar and what he has to offer. I've bitten my tongue on this for days after reading this thread and come to one opinion that people do not want to know what Jose wants and also are so blinded by past achievements of Mata that he can do no wrong. Mata was sublime last two seasons, two seasons yes, but now we have a different manager that wants a different system and certain players to change and adapt. Nobody's place is guaranteed right now, possibly only Oscar's, this team is being steered by a new sailor, if the crew on board aren't ready to work the crew will be thrown over board. Either adapt to what he wants, fight for the place because it wont be handed on a plate to you.