The 28 year old Spanish and Manchester United midfielder thinks that everyone is expecting too much from the French international for his big money move to the Old Trafford.
Mata defends his fellow team mate Paul Pogba and claims that at this moment people cannot compare him with Lionel Messi and Cristiano Ronaldo.
At the beginning of this season the Manchester United brought Pogba back into their squad with a world record fee of €105 million from Juventus and because of that, people are expecting something magical from him but this season sometimes he failed to do so for the Manchester United.
Juan Mata thinks Pogba is not under performing this season for them, but the people are expecting something unrealistic things from him.
In an interview Mata said: "I imagine it is not easy,"
"When the big transfer comes and the expectations are high, sometimes people lose perception of reality.
"We are not machines. Messi and Ronaldo are the only two [that can score every game]. There is no more."
This Sunday the Manchester United side will play against the Southampton side in the EFL cup and he is standing on the verge of winning the first major trophy with his teenager club.
This season under Mourinho the 23 year old youngster Pogba has made 36 appearances in all the competition and he has scored 7 goals so far for them.