The Dutch midfielder has called on his team-mates to finish the Premier League season by winning their remaining games ahead of Mancini's side's trip to Swansea on Sunday
The Netherlands international has rubbished suggestions that Roberto Mancini and the players are feeling any pressure being put on them by fierce rivals Manchester United, who are only two points behind.
The blue side of Manchester make the trip to Swansea on Sunday, where only the red side of Manchester and Norwich have so far come away with all three points.
De Jong told The Sunday Mirror: “It has come down to the last 11 matches. We have 11 cup finals – and so have United. From now on, every game is a final.
“We can’t afford any mistakes because we know that United are right behind us. Can we feel them? Not really, we just look at the table and see the gap is just two points.
“United are two points worse off so they also know that any mistake could really hurt their chances. It is brutal. What we must do is concentrate on us rather than them.
“If we win 11 games then we are the champions. People talk about pressure. But pressure is only what you put on yourself.
“United haven’t put us under any extra pressure. They have been right behind us all the way.
“They have won some good games recently, but we expected that. We are prepared for this fight to go all the way to the very end.
“United are United. They are not going to give up the title easily, but they must know that they are in for a big battle from us.
“We aren’t going to go away either.
“We’re not thinking of the derby at the end of the season. What is the point of that? We start with Swansea and we take it from there.
“It is going to be tough.
“Swansea are new to the Premier League, but they have shown that they are good enough for this level. We have to take care because beating the leaders would be a massive result for them."
City will make the trip to Wales without inspirational captain Vincent Kompany who picked up a calf injury in Portugal in the week, but they can welcome back Yaya Toure who was suspended for the 1-0 defeat by Sporting Lisbon.
The 27-year-old added: “Any team would miss players like Vinnie and Yaya. They are both great players, but they are also very big influences in the dressing room.
“But we have got leaders all over the pitch. This is a big squad, with experienced players in every position.
“We don’t lack character. We have an unbelievable amount of points at this stage of the season and you have to accept that United have done a great job keeping up the challenge.
“We all have to step up to the plate from now on – and I think we will.
“One defeat in the Europa League at a place like Sporting Lisbon is not a big crisis. We still have an opportunity to go through to the last eight when we play them at home."
Mario Balotelli has often been at the centre of headlines for all the wrong reasons, but De Jong believes he can be the key man for City in the run-in.
“Mario is a big character in the team. He is still very young and he wants to enjoy himself,” he said.
“He looks unhappy sometimes even when he scores, but the players will tell you that he is always looking for a laugh.
“Maybe [it's] because we laugh at the things he does that he keeps doing them. He goes from one thing to another.
“I think there are signs that he is learning about when to joke and when to be serious. Mario is Mario, but he can be very important to the team.”
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