The Blues take on Ajax on Tuesday, followed by another home game against Real Madrid before a trip to face Borussia Dortmund to complete the group stage games.
City need maximum points from those remaining Group D games to progress into the knockout stages of the competition and Nasri says the belief is strong that this can still be achieved.
“Of course we believe,” said Nasri, who scored City’s only goal in Amsterdam. “It’s about now we need to think back to last season and how everyone thought it was impossible for us to win the title.
“We kept believing right up until the final minute of the season and we will do the same again now. Three wins will take us to the next stage – we know that it will be tough - but we are more than capable of doing it.
“We have the quality, there’s no question about that, but we also have the next two games at home where we are unbeaten in the Premier League for a year so there is everything to play for.”
Nasri says Ajax’s performance didn’t surprise him in the first meeting between the clubs which, of course, the Dutch champions came from behind to win 3-1.
“We knew they were a very good side who play great football and have done since the 1970s,” he said. “They have a philosophy to play a certain way and always have good footballers to continue that tradition.
“Normally, we would have come away with a win because we are a better team than they are, but on the night, we didn’t play well they played better than us and showed us how to play.
“It was a lesson for us and one that we will learn from. We know that we have to beat them if we are to keep our hopes alive so we will need to be at our best. We can’t afford another off-night.”