Juan Mata
Juan Mata says his friend De Gea is focused at United. Getty

Juan Mata has claimed that David De Gea remains "calm" at Manchester United despite the new rumours linking him with a move to Real Madrid. Meanwhile, the former Chelsea star said that he is also very happy in the Premier League but would like to return to La Liga at some point to hang his boots in Spain.

Reports in Spain in recent days have claimed that Real Madrid have earmarked the signing of a keeper as a top priority for the coming transfer window, with both De Gea and Chelsea number one Thibaut Courtois named as the two high-profile alternatives to replace Keylor Navas.

De Gea himself said earlier this week that he is "happy" at Manchester United, but admitted "nobody knows the future".

Mata has now admitted his surprise about these reports as he claimed to know nothing about them.

"Have (those rumours) come out again?" Mata said to Cadena Ser. "The truth is that I did not even know that there were rumours again. Once the summer (of 2015) passed, which is true it was hectic..."

And questioned whether De Gea has already ruled out a future move to Real Madrid, he added: "I do not know, but we have not talked about it. I didn't even know that there were new rumours about that ahead of the coming summer. He is calm, and with many fronts still open this season, without thinking about the summer."

The former Chelsea star, meanwhile, said that he is leaving one of the best seasons of his career at United, but refused to give a grade until the end of the campaign.

"It's being a good season for me. We have to value if it's the best (since I came to the Premier League) at the end of the season, because it also depends on the team and whether we get titles. But I'm very well, playing a lot, helping with goals, assists. I am at a good moment in my career," Mata added.

Yet, the Spanish international is already 28 years old and admitted that the idea of returning to La Liga one day is starting to be in his mind. He is happy in the Premier League and still has a contract at United until 2018 but asked about a potential move back to his homeland, he said: "I do not know. I have no idea. It is true that I have been here six years and I am happy in the Premier League and in England. But I'm Spanish and I love the Spanish football...

Questioned whether he would like to retire in his homeland, he added: "The truth is, yes, but I do not know what will happen. At the moment, I just wish from the distance that Oviedo can go up to the first division and that the Sporting stay in La Liga and because I want the two teams of Asturias to play in the top flight."

Meanwhile, Mata reiterated that his relationship with Jose Mourinho is good, despite leaving Chelsea to join Manchester United in January 2014 after failing out of favour with the Portuguese boss at Stamford Bridge.

"Mourinho is fine. He has come with the idea of returning United where this clubs deserves to be and we are now trying to do that," he said. "My relationship with him is normal. I have already been with him here more time that I was at Chelsea. We speak more, there is a group of Spaniards in the club and he has a lot of communication with us. He has to make decisions and I have to do my best. It's the same Mourinho I had at Chelsea. People do not change from one day to another,"

"We are still in the same position but we have reduced the gap with the top. Chelsea are doing very well, they have an important advantage but we have the target of getting into the top four to play the Champions League next season. And we also have the chance to win the League Cup against Southampton this month. We are also in the FA Cup and the Europa League so there is still a lot to do this season."