Andreas Pereira has scored one goal and has three assists in 10 Liga games this season. Photo by Manuel Queimadelos Alonso/Getty Images

VALENCIA, Spain -- Andreas Pereira is expected to play in La Liga's biggest game of the season so far on Sunday, when second-placed Valencia host leaders Barcelona.

Few expected Valencia, who Pereira joined on a season-long loan from Manchester United on transfer deadline day in August, to show such thrilling form. Los Che are six-time Spanish champions but have been an unstable, lurching giant in recent years, finishing 12th in each of the last two seasons and working through 12 coaches in five years since Unai Emery departed in 2012.

The improvement has been vast and the mood at the club's Paterna training ground, where Pereira talked to ESPN FC, is as bright as the year-round Valencian sun.

"It's going well here," says the Belgian-born 21-year-old. "I had to adapt at the start because it's a different style of play to how I played at Granada [on loan last season] and also at United. We play a 4-4-2 system here, but it wasn't just the football. I'm at a new club with new people in a new city. The football adaptation is the quickest part because I was in La Liga last season. I already spoke Spanish, too. But I'm settled and playing well, like the team. I have a house close to the training ground and I'm friends with Gabriel, Neto and [Goncalo] Guedes, the Portuguese speakers."

New Valencia coach Marcelino excelled at nearby Villarreal before a disagreement led to his departure at the start of last season.

"He's a great manager, working with a very talented group of players here," says Pereira. "We're not only together at the training ground, we go for meals together, we also do activities together, like playing paddle (tennis) recently. It all helps build a better team spirit."

That's evident on the pitch and has translated into form that sees Valencia, who have won nine of their 12 league games, sit six points clear of Real and Atletico Madrid.

"We play very good football with an explosive counter-attack," says Pereira. "The manager demands this and pays incredible attention to detail. If something goes wrong then he tells you. I lost the ball in one game and was thinking: 'Damn! I've lost the ball.' The manager doesn't want me to think; he wants me to press immediately, to focus without hesitation. We have a very young, talented, squad. The players are very ambitious. They want to prove people wrong. Last year was not a good year for Valencia. They're determined to change that this year."

There are other factors, such as Valencia's clever use of the loan system. In addition to Pereira, Guedes was borrowed from Paris Saint-Germain, while Jeison Murillo and Geoffrey Kondogbia are owned by Inter.

United manager Jose Mourinho wanted to keep Pereira at Old Trafford this season after he impressed on the club's preseason U.S. tour, but Pereira decided to move.

"I wasn't going to be a starting player at United this season," he explains. "I felt that by coming here I would play more minutes. By playing I'll get better, I'll evolve. That is better than being on the bench where I get frustrated and it starts to work against me. Here, I'm playing, I'm happy and I'm getting better. People see that, United see that, and it will help me, Valencia and Manchester United. If I go back then I'll be a better player. I'm under pressure here, but in a positive way," says Pereira. "I play against big teams in big stadiums. We're second in the league."

And so, instead of being a first-team substitute at United or turning out for the reserves in front of crowds of 1,000, Pereira will face the likes of Barcelona and Real Madrid, that latter of which United met in August's UEFA Super Cup.

"[Madrid] were very good," he says. "The players spoke after the game and said: 'If we do everything right then we can get to that level.' I think with the players at Old Trafford that United can do that. United are stronger in Mourinho's second year. In the first year, there was a big change with the new manager. It was totally different than under Van Gaal.

"They're two great managers, but Mourinho is more relaxed off the pitch," continues Pereira. "Of course there is discipline and you have to be on time but players are more relaxed. They feel good. There's less pressure because Mourinho takes it off the players and puts it on himself. During the preseason in Los Angeles, he told us that we could do whatever we wanted after training. He trusted us to rest and relax. To do what we wanted to do. There were a lot more meetings under Van Gaal."

Pereira scored his only Manchester United goal vs. Ipswich in the League Cup and has played 13 times for the club. Nigel French / EMPICS Sport

Despite his unhappiness that Pereira opted to leave for Spain -- managers usually want as many players as possible at their disposal -- Mourinho follows his progress and keeps in touch by text.

"We have a good relationship," says Pereira. "We usually speak in English in front of the group but sometimes, if we are alone, in Portuguese, like when he was angry! He encourages everyone to speak in English, though if there's a player who doesn't speak so good English then he'll explain in Spanish. He's knows different languages."

Pereira is also in contact with several of his United teammates, including his namesake Joel.

"I used to live with Joel," he says. "He is very good. He'll soon be the No. 1 goalkeeper of Portugal. He's that good. People don't know him because he's not playing, but as soon as he starts to play they'll see. He's very agile, has excellent reflexes, he's sharp and a little bit crazy. He's not scared of anything and it's good for him to learn from David [De Gea] and Sergio [Romero], two very good goalkeepers who are professional and the right people to learn from.

"David is also a close friend," continues Pereira. "He's amazing; the best goalkeeper in the world. People see what he does in games, but we're lucky to see what he does in training. Sometimes we stand there and think: 'How did he save that?' Paul Pogba is another friend I keep in touch with. He's special; very charismatic."

Pereira also admires the contribution of Marouane Fellaini: "He's very important for United. It's very useful to have someone like him in your team because he takes off the pressure. He gives everything, takes the ball down, he fights for the team. He's a very good guy and he sent me a message a few weeks ago to ask how I was."

Pereira joined United in 2012 and has settled in to a city that, he says, "feels like home."

"I have friends in Manchester, some of them go to the away games with United and they were sad when I left to go on loan," he says. "My family are there: My mum, dad and sister. My sister studies in Exeter but, when I go back to Manchester, I know the club and everyone there.

"I came to the club at 16-years-old when I was very happy at PSV Eindhoven. I was there for seven years, the captain at every age group. United's Belgian scout knocked on my door and I was invited to Carrington. I met Sir Alex [Ferguson]. He said 'Hi' in Portuguese, which amazed me. Then he said that he always had space for a Brazilian in his team and at that moment I thought: 'I want to play here!'"

In August 2014, 18-year-old Pereira made his United debut but the League Cup tie at Milton Keynes Dons ended with an ignominious 4-0 thrashing.

"I was happy to be selected, but nervous too," he says. "(Assistant manager) Ryan Giggs went mad with the players after the game. He was right because the performance wasn't United's level."

The Pereira family had moved to Europe because of Andreas' dad Marcos, who was also a professional footballer.

"My father moved to Belgium to play in the first division," says Pereira. "He was a very good player, someone I looked up to, but he was unlucky with knee injuries. He was a winger and I wanted to be the same as him. I watched him every week. He was fast and strong, different to me because I'm not as fast as him but I am more technical."

So, what is Pereira's best position?

"As the second midfielder, a No. 8 or a No. 10," he says. "I can play as an attacking midfielder on the left or right wing."

"Andreas came as a big talent who could do a bit of everything," says former United youth coach Paul McGuinness. "He can score, he can shoot with both feet, he can take free-kicks and corners, create goals and be a crowd pleaser. He's a playmaker, an inside forward, although he can play up front. He can beat people. He's a player who could come back to Old Trafford and be a star.

"He has real belief in himself, he's very confident in his own ability and he has a lot of ability. The top players have that. I had him when he was undergoing the transition from schoolboy to professional. He was used to being the star man who wanted to show his talent, to be man of the match all the time. Andreas has rhino skin, he can take disappointment. I left him out of one game - an odd decision because he was the best player. I wanted to see his reaction. He didn't sulk.

McGuinness added that he wouldn't be surprised if Pereira "came back to United to be a star." So, where does the man himself want to be at this time next year?

"I want to be playing," says Pereira. "I want to keep developing, keep progressing and keep doing well at a high level, the highest level I can. I want to be important at a big club. United has always been my dream and it will always be my dream."

Internationally, meanwhile, Pereira played for Belgium at Under-15, 16 and 17 levels, before switching to represent Brazil's Under-20s, for whom he scored in the final of the U-20 World Cup in 2015, and 23s.

"We speak in Portuguese at home," he says. "My family is Brazilian and I feel Brazilian, even though I have never lived there. I was born and raised in Belgium so I also feel Belgian. I feel the blood of a Brazilian, but I understand both ways. It's not so unusual for people to move around the world now. We go on holiday to Curitiba in Brazil, where my family is from. My friend Anderson, who was at United, plays there now. I spend the holidays playing football with family. We play from noon until 8 p.m. Only football."

A place in Brazil's World Cup squad looks to be unlikely for Pereira but, with Barcelona on the horizon, he has plenty of things to look forward to.

"I'll just keep doing what I'm doing," he says. "Working hard, improving and following my dreams."