Juan Mata: I've never had a bad relationship with Jose Mourinho

Juan Mata says he has never had an argument with Jose Mourinho and insisted he is happy working under the 54-year-old at Manchester United.

Mourinho was in charge at Chelsea when Mata was sold to United in a £37.1 million deal in January 2014.

But the Spain international has become a key part of Mourinho's squad at Old Trafford this season, and he says there was nothing personal behind his exile at Stamford Bridge.

"What has changed is the context of the club, the squad and the way that each team plays. I have never had a bad relationship with him," Mata told El Pais. "We have never had an argument. We have a normal relationship.

"Simply, it is that in Chelsea he wanted to play in a certain way and in United there is another set of players who mesh better with my characteristics. But we are both the same people, we have not changed."

Asked for his idea of the ideal coach, Mata said: "He should be a leader in good times and bad and he should strive to get the best out of each player. It is complicated but to deal with personalities is almost more important than tactics or fitness.

"You must have the capacity to motivate the players and you must have positive communication with them, and the environment surrounding the team also has to be positive. People express themselves better when they feel comfortable. It is like that in all jobs, even football."

Mata returned to the substitutes' bench for the 1-1 draw against Swansea on Sunday after missing eight games with a groin injury.

He is set to return to the team for the Europa League semifinal first leg with Celta Vigo on Thursday.

United are favourites to book their place in the final in Stockholm later this month, but Mata had a warning for his teammates.

"We have watched the videos and analysed their [Celta's] game, which is fast-moving," he said. "They have talented players and are intense in defence. The coach has impressed upon us the importance of this semifinal, for our fans and for the city, so we must be at our best to beat them.

"Personally, I feel like they are going to be tough to beat because they mark each player and they are quick in attacking. For us, our expectations are the same in each league we play and we face each tournament with humility and hope and obviously with the goal of winning everything."

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