We can win the group now beams Mancini

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"It was important for us to win this game," said the City manager, who wildly celebrated the winner. "I hope this will be very important. It was important to win the first game in Champion League and now I think anything can happen in this group in terms of first place.

"At the moment Bayern Munich have seven points, Napoli five and us four. It's open for the first and second places.

"The goal came from our last chance. I think in that moment we were lucky and you need to be lucky to score in the last seconds.

"Yes, probably it would have been very difficult to qualify if we had not won. The situation would still have been open, but now this is much better."

Mancini feels City's fate hinges on their game away to Napoli on November 22

"Yes, 100 per cent," he said. "I think that game will be very important. Before this we will play the game in Villarreal and it's important we take all the points there.

"But the game in Naples will be the crucial game. I don't know for which position, but first place is open."

Mancini also claims winning with the last kick of the game is the perfect boost for his side going into Sunday's derby against Manchester United at Old Trafford.

"It was important for the Champions League," he said. "The derby will be a different game, another situation. But it's good for our confidence and it's important to go there and do well because it will be very hard."

Mancini also defended his bold decision to haul Adam Johnson off before half-time with City trailing, claiming the England winger understood his call to replace him with Gareth Barry.

"I spoke with him and he understands," he said. "Every manager can decide if the team needs a tactical substitution and unfortunately players have to leave the pitch and will be disappointed, but Adam is a very important player for us.

"We were conceding four or five counter-attacks and didn't have many players in the middle. I wanted to move Yaya Toure behind Edin Dzeko.

"It was not because Adam did not play well and he did play well. It was a tactical substitution."

Mancini was reluctant to discuss the outcome of tomorrow's investigation into Carlos Tevez's alleged refusal to play as a substitute in last month's Champions League match at Bayern Munich.

However, he intriguingly added: "I'm soft because I'm a good man and I can't understand everything but I would prefer not to speak about this situation."

Villarreal coach Juan Carlos Garrido admitted defeat was hard to take.

Garrido said: "I think we have done a good match and we did deserve - if not to win - a 1-1 (draw).

"I thought we had a good match in general, in all aspects, and to lose in the last minute in this way is difficult.

"Congratulations to City because they won but we thought we deserved more from this match.

"My players thought the goal was offside but it was not offside. They thought it was unfair to lose this way but we must accept it."