Ninety minutes with Juan Mata is a time full of space and light. It’s a little like watching him play football, where his intelligence and vision are obvious, but Mata also arrives at a small hotel in Altrincham with a minimum of fuss. He is alone, without an agent or a sponsor, and interested in a detailed conversation rather than a routine interview.

The importance of space becomes even clearer when we turn to Saturday’s visit of Mata and Manchester United to Anfield. Second in the table, just behind Manchester City on goal difference after both clubs have won six and drawn one of their opening seven Premier League games, United face their first real test against a bitter rival in Liverpool. Mata has prospered before at Anfield, most notably when scoring both goals, including an acrobatic volley during a 2-1 defeat of Liverpool in 2015. It was a volatile afternoon marked by Steven Gerrard being sent off for a stamp 38 seconds after coming on as a substitute.

Saturday could be as intense and physical but Mata smiles after being asked what he thinks when the mayhem of a Premier League game bursts open. “I love it,” he says with unexpected relish for a slight figure who plays such technical football. “When the game gets crazy, it creates more space. It is a very physical league which is big on set pieces – but that sense of ‘Let’s forget about tactics and just attack’ helps me use that space.

“For me good football is not about how many skills you show or how many players you beat. It’s about making the right decision every time you have the ball. I see players that make 100% right decisions – Iniesta and Xavi – but there are also good English examples. Scholes, Lampard and Gerrard made many more right decisions than wrong decisions. You see so many players with physical qualities. They are quick and strong but they don’t make the right decisions. So for me the most important thing is to do what the game asks from you in the moment. You naturally know what is right which is why, even though you have to think about defensive duties and structure, once you’re on the pitch you have to be free in your mind.”

Such free thinking, and a compassionate ability to understand what footballers can also do off the field, underpins Mata’s landmark project Common Goal, which he launched in August. The Spain international, who has won the World Cup, European Championship and the Champions League, will donate 1% of his salary to Common Goal so that the money he and others raise can support football charities around the globe. Mata’s grand ambition is to reach a position where 1% of football’s entire multibillion dollar industry is donated to charity.

Quick Guide Common Goal: some of those who have signed up so far Show Mats Hummels Bayern Munich and Germany defender, left, was first to join initiative. 'I’m putting the call out to all my fellow footballers,' he said Alex Morgan USA World Cup winner, Orlando Pride striker, said she was 'thrilled' to sign up next with her international colleague Megan Rapinoe

Megan Rapinoe Seattle Reign midfielder said: 'Myself and Alex felt it was important that women’s football was represented from the outset'

Giorgio Chiellini Juventus and Italy defender contacts by email to join the project. 'Hello. I’m Giorgio Chiellini, player of Juventus,' it begins

Serge Gnabry The 22-year-old, on loan at Hoffenheim from Bayern Munich, becomes the sixth and youngest member of the team

Dennis Aogo Stuttgart’s former Germany international says he will donate two per cent of his salary. 'I asked myself: "Why only one per cent?"'

Alex Brosque Sydney FC captain, who had a spell with Feyenoord, is the first to sign up from outside Europe and the United States

Julian Nagelsmann The 30-year-old Hoffenheim head coach has become the first manager to sign up to the initiative Hasan Ali Kaldırım The Fenerbahce wing-back says he is 'proud to be the first Turkish player to make the pledge' Alfie Mawson Swansea defender and Bournemouth's Charlie Daniels become the first British players to sign up Charlie Daniels The defender says it 'seems right that our national sport gives something back to society'

“This is not about me,” Mata stresses. “Someone had to start and I did. But I hope a lot of us will commit fully to the project. The ultimate goal is that everyone related to football, including the media and fans, can help in different ways. The best way to start is with players because we bring greater attention. We are talking about 1% because we need a realistic structure that encourages other people to join. My own 1% doesn’t mean so much but if, one day, we reach 1% of the whole professional football revenue it will be great. And if people are financially not in a good situation they can join by spreading the word.”

If Mata is driven by a communal vision of football helping to transform society, the roots of his commitment are deeply personal. He remembers how the loss of his grandfather eight months ago sparked a desire to try to improve less fortunate lives. “It was a very sad day,” Mata says of his grandfather’s death. “He used to take me to training and watch all my games. Football was his passion and he was very happy he had a grandson that he could live football through. It meant a lot that he came to see the World Cup final and some Champions League finals. Obviously when I play well and win a trophy I feel happy about myself. But I feel even happier for my family because I know how they suffer when things are not going right. They suffer more than me. And they are probably happier than me when things go well.

Juan Mata scores a spectacular volley during Manchester United’s 2-1 win at Anfield in 2015, under Louis van Gaal. Photograph: Peter Byrne/PA

“The night before he died we played Saint-Étienne and I made the assist for the Mkhitaryan goal that won the game. It was a Thursday and I was hoping to see him after the Capital One Cup final on the Sunday. But he died on Friday so I went to Spain on Saturday and came back for the final. We spoke one last time after Saint-Étienne. He was very weak but he said I made that nice assist. It’s probably the assist I will remember my whole life. He was very important for me also in thinking about football as a powerful tool to make so many people happy.

“I had been thinking about doing my own foundation to help others. But I was also encouraged by my sister. She has a great personality and lives in Iceland now. She’s a traveller, a free soul and I admire her way of living. So my family gave me the right mentality to think about football in a new way. I then met Jürgen Griesbeck [the founder of streetfootballworld, which now runs Common Goal]. He’s been working in football for 15 years and he started in Colombia after the death of Andrés Escobar [who was murdered] because he scored an own goal in the 1994 World Cup. We clicked and came up with the idea of bringing football together to help others. The idea is that it doesn’t have to be voluntary. We aim to have the 1% donation [embedded] within the structure of football.

I understand why some people think footballers are selfish.

“It’s not easy to put the idea into reality but Jürgen had the background and I had the belief and the contacts to communicate the message that the power of football is unmatchable. Wherever I go, I see kids playing football. Even if there is no grass and it’s just sweaters for goals you see how people love football.”

So far six other players – Mats Hummels, Giorgio Chiellini, Serge Gnabry, Dennis Aogo and two US women internationals, Megan Rapinoe and Alex Morgan – have joined him in publicly pledging 1% of their salaries to Common Goal. Alex Brosque, the Sydney FC captain, has also just been confirmed and on Saturday one of the most intriguing young managers in European football will also join Common Goal. The first English footballer to support the initiative will also be unveiled soon. “We have more players that will be announced step by step,” Mata says. “We want to make the publicity long-lasting and not just sporadic. We also want to show it’s a global project and we have players from five continents. The response from everyone has been great – journalists, fans, my team-mates and other professionals. Sometimes we football players need a little push but as soon as you explain the project they understand. Our goal is to make it easy, efficient and transparent. So many players contacted me after they’d seen Common Goal and wanted to join straight away. That was such a happy moment. We’ve also had promising conversations with people that make decisions in football. I feel they’re keen to do this with us.”

Even if it takes years, does Mata believe that the aim of football donating 1% of its total revenue can be reached? “It doesn’t matter how long it takes. Sooner or later, I think it will be done.”

Mata has not yet spoken to José Mourinho, his manager, about the initiative. “Sometimes it’s difficult to get out of the routine of preparing for matches to think about these things. So maybe it’s a conversation for the off-season. It’s just a matter of finding the right moment to communicate with everyone.”

After their difficulties at Chelsea, where Mata was sidelined by Mourinho, it is striking how much has changed. Mourinho recently said: “I need Mata’s brain” at a resurgent United. “As a team we are playing with more confidence and more solidly than anything at United since I came here [in January 2014],” Mata says. “It was a difficult period after Sir Alex with three managers and 15 new players. But we are close to the consistency we want. We know United fans want exciting football and this season, especially at Old Trafford, we are scoring lots of goals. And, personally, I’m in a very good moment. I’m 29 so this is obviously the second part of my career. But I feel I have many good things to give.”

Having worked with Mourinho, amid completely different experiences, what defines his manager? “His hunger to win,” Mata says appreciatively. “And he has a clear picture of what he wants. People can disagree but he knows how things should be done. He has a strong character but you have to know him to really appreciate him. Since he came to United we are much closer and I know he loves to compete and win big games.”

Mata remembers the ordeal he suffered under Mourinho at Chelsea after he had been the club’s player of the season the two previous years. “He was keen to play a different kind of football and that was fair enough. But it was difficult for me after winning the Champions League, the Europa League and being player of the season. One of our ultimate goals is to feel loved and wanted so it was a psychological challenge. I was not free but, when you’re feeling that kind of blocked moment, just take the ball and play. Let it flow.”

Having lost his flow at Stamford Bridge did he discuss his situation with Mourinho? “No, we didn’t speak about it. We never argued but it became more and more difficult for me. The best option for everyone was me joining Manchester United. Now, it’s nice for me personally to see how we are reunited. So many people suspected personal problems between us but there was nothing like this. Now I’m playing a lot. I’m feeling important to the team and I have a good relationship with José on and off the field.”

Jose Mourinho and Juan Mata at Chelsea. ‘So many people suspected personal problems between us but there was nothing like this’. Photograph: Ian Kington/AFP/Getty Images

At first, Mata’s mood must have dipped when he heard Mourinho was arriving at Old Trafford 16 months ago? “It was another challenge but my desire and my professionalism is not questioned. I know he likes that. I also think my football can add good things for our style. So I believe: ‘OK let’s try again. Let’s give the team what he wants me to give.’”

In Mourinho’s first competitive game as United manager Mata came on as a substitute in last season’s Community Shield – only to be substituted himself. “Yeah,” he says with a grin. “But it didn’t bother me. The only thing that bothered me was that some people tried to make it bigger than it was. You have to know how he thinks. I do. It was a game where he had six substitutes. I went on to the pitch [in the 63rd minute]. We were winning and in the last two minutes he thought: ‘I have one more substitute [Mkhitaryan] so why shouldn’t I use him?’ He put on the taller guy because he was being practical. I didn’t take it personally.”

This season, with Mata injecting a silky intelligence into Mourinho’s muscular team, United and an exhilarating Manchester City look set for a mighty battle. “It seemed like this last season. But then Chelsea took over. It seems that both United and City are strong this season and Liverpool, Tottenham, Arsenal and Chelsea have dropped points. But it’s early days and I still see these six teams fighting for the trophy. Let’s see who can be more consistent.”

The managerial contest between Mourinho and Pep Guardiola will almost be as fascinating as the clash between Manchester’s contrasting teams. Does Mata see much of Guardiola? “I’ve never bumped into him in Manchester which is unusual because it’s not a massive city and he lives in the town centre.”

Mata’s father owns a Spanish restaurant, Tapeo & Wine, in Manchester – and it is tempting to think he and Guardiola might share a few philosophical nuggets over some tapas. “He did go there,” Mata says. “Mourinho did as well and some of my team-mates and some City players. I go a lot and I was there when José was there with team-mates and staff. I’ve seen some of Pep’s assistant coaches there, like [Mikel] Arteta – but I never bumped into Pep.”

In a more sombre mood, Mata is reluctant to talk in detail about the distressing scenes when people supporting independence in Catalonia were assaulted by Spanish police. “It’s not great when you see confrontations. I had sad and worrying feelings but I hope it can end in a good way with no violence. I hope some kind of resolution will be possible, through dialogue and goodwill from both sides.”

Has he spoken to Gerard Piqué since Barcelona played Las Palmas behind closed doors? “No – but football plays a very important role in Spain and Catalonia. It has the ability to unite people like little else.”

Juan Mata, left, and Santi Cazorla celebrate after Spain won Euro 2012 by beating Italy 4-0 in the final. Photograph: Denis Doyle/Getty Images

Mata hopes to secure a place in Spain’s World Cup squad next year – as he has played in the last two tournaments. “It’s a new generation, a new manager and new quality. But I see myself as part of that. There’s good competition to get into the side – but during all my years in the team there was good competition and I was doing it. I am the same player with a massive club, playing week in, week out, and performing well. So I believe in myself.”

Are United ready to compete with Real Madrid and Barcelona? “In the Champions League it’s different because, at the knockout stage, you don’t need that Premier League consistency every week. You just need to compete really well in those two games. I remember playing a semi-final at Chelsea [under caretaker manager Roberto Di Matteo] against Barcelona. The other semi was Bayern and Real. Everyone spoke about a Real-Barça final. But Chelsea beat Bayern in the final. We were the underdog but we won.

“You need a bit of luck in the Champions League but the additions of [Nemanja] Matic, [Romelu] Lukaku and Victor Lindelof are important. Matic is great and his physical appearance and quality on the ball helps so much. Victor adds youth and quality in defence. Lukaku is scoring a lot and with the addition of Zlatan in the second part of the season we have a balanced squad. Good people in the dressing room, good mentality and let’s translate that into something special.”

Mata has played alongside so many great players but he says: “If I consider the best footballer I played with, I look at someone that was not particularly quick, strong or tall. Iniesta. When we played for Spain he always passes the ball to you in the right moment. He always makes you better. It was the same with Zidane. His individual qualities were incredible. When I was in Real Madrid reserves I used to train with Zidane, Ronaldo, Beckham, Raúl. All great players but Zidane made everyone look better.”

If I consider the best footballer I played with, I look at someone not particularly quick, strong or tall: Iniesta

We discuss the new National Football Museum exhibition of photographs taken by him and his girlfriend of children playing in India before returning to the power of football. “I’ve been lucky to be born in Spain to a good family,” Mata says. “But some team-mates reached the same position from a tough background. Football is equal and it doesn’t matter where you come from. I have two team-mates now, Eric Bailly and Marcos Rojo, and their roots are completely different to mine. One is from Cote d’Ivoire, one is from Argentina. They were born in humble families with few economic prospects. They played football with their friends and now they’re at Manchester United. It’s a beautiful example of people that were not as lucky as us doing great.”

After the interview we keep chatting and Mata tells me about the latest book he is reading, Autobiography of a Yogi, which he picked up while in India. I’m about to ask him what he thinks of Paul Auster’s new novel when his phone beeps. Ander Herrera, his close friend and team-mate, is waiting outside to drive them to afternoon training – which is earlier than usual.

Mata looks briefly flustered. He is too professional to be late for training but he feels duty-bound to give up some time for photographs. “You’ve waited a long time,” he says, apologising to the photographer. And then, with familiar grace and practicality, Mata explains the situation to Herrera and offers a burst of concentration to the photo session. Everyone is happy and the man behind the extraordinary Common Goal project finds space for one last observation before setting out to do more good on and off the football field.

“I understand why some people think footballers are selfish. But people also underestimate football. When good comes out of it then it is a very fair sport. If you have the talent and dedication you can do well no matter where you come from. In that way football is like boxing. It gives hope to so many people. It’s incredible what football can do to change lives.”