Manchester United v Manchester City: Roberto Mancini delighted with performance and says his side 'can improve'

City beat United 2-1 at Old Trafford

Manchester City boss Roberto Mancini felt his team had proved a point - but not reignited the title race - by beating rivals Manchester United.

Sergio Aguero came off the bench to score a superb winner as City deservedly edged a tight affair 2-1 against the Barclays Premier League leaders at Old Trafford.

With United still holding a 12-point lead over their neighbours with just seven games remaining, Mancini has not changed his opinion that City's spell as champions is coming to an end.

But having insisted prior to the game the table was not a true reflection of the difference between the sides, he was pleased his team had proved it.

The Italian said: "The championship is finished but we deserved to win because we played better, we played good football. We didn't take any risk.

"We know that we can win the title next year. This year we did some mistakes but we can do nothing now. The season is gone.

"It is important we continue to win because we have another seven games but it does not change anything for the future.

"We need to continue to play like this for next season.

"We have two or three months where we can work well, where we can improve our team.

"I think we showed here we can't be 15 points behind."

City went ahead when James Milner's deflected strike found the net after Gareth Barry had robbed Ryan Giggs early in the second half.

Phil Jones forced an equaliser when he headed a Robin van Persie free-kick in off Vincent Kompany but Aguero had the final word 12 minutes from time.

Even though the title is all but gone, City celebrated in a manner that suggested the result meant much.

As well as laying down a psychological marker for next season and restoring some pride, it was the first time the club had secured back-to-back wins at Old Trafford for 41 years.

Mancini said: "This is important for us because we can get second position.

"Maybe we have one game in hand and if we win the game against Wigan we go 10 points in front. After that maybe we don't have a problem.

"This is for our supporters because they deserve this victory. After being 15 points behind it was important for them."

City's attention will now turn to their FA Cup semi-final against Chelsea at Wembley on Sunday.

Playmaker David Silva is doubtful after being forced off late in the game.

Mancini said: "I think it is a hamstring injury. Maybe it is not so bad but I don't think he will be ready for Chelsea.

"Chelsea are in a good moment, they play well and it will be difficult.

"It will be a good game, probably, but it will be different. Semi-finals are different from championship games."