City were punished for the early sending-off of Dedryck Boyata as rivals Arsenal ran out 3-0 winners at Eastlands.

The result saw City drop two places to fourth in the table as both the Gunners and Manchester United overtook them on goal difference.

Yet Mancini was still happy with the performance of his side, who remain five points behind leaders Chelsea, after playing for 85 minutes with 10 men.

The Italian said: "It is a situation that can happen.

"It was a bad result because we lost, but after the sending-off everything changes.

"Clearly it would have been better if we had won the game but if you play with 10 men against Arsenal it is difficult.

"It is important we had the mentality during the game that we always tried to play.

"I am very proud of my players because we showed we are one of the best teams in the Barclays Premier League.

"They played like a strong team, they played well. We lost but the way (ahead) is long."

City had started brightly as Carlos Tevez broke clear to create a chance for David Silva but Lukasz Fabianski produced the first of several good saves to deny the Spaniard.

The game's defining moment came in the fifth minute as Boyata, as the last man, was shown the red card for bringing down Marouane Chamakh.

Arsenal capitalised to go ahead through Samir Nasri and it needed a brilliant Joe Hart penalty save from Cesc Fabregas, after Vincent Kompany needlessly felled the Gunners star, to keep City in contention.

Alex Song put the result beyond doubt when he pounced inside the box after 66 minutes and substitute Nicklas Bendtner added a third with a brilliant finish late on.

Mancini played down fears that talisman Tevez, who was substituted early in the second half, had suffered a serious injury which would have made a bad day for City even worse.

"He took a knock on his muscle in the first half in a tackle but it is not a problem," he said.

Arsenal's performance should put to rest criticism of their recent record against the sides now considered to be title rivals.

The Gunners had won only three of their previous 17 games against either City, Chelsea or United.

Manager Arsene Wenger said: "It was important to get that off our shoulders - you feel the tension if you don't do it.

"It was important to us to get a win in a big place, to strengthen belief of the squad and continue our march forward.

"I hope that will give us the belief and confidence to take into other games."

The match might also prove a breakthrough for the much-maligned Fabianski, who showed confidence and composure throughout.

"From game to game, he shows what we see in training," Wenger said.

"Sometimes in our job you have to be steady and fight against opinions.

"It is easier when you know a player has the talent and I believe he has the talent."