Vincent Kompany has said that Manchester City will be "unsatisfied" until they are successful in the Champions League.
City have never progressed past the last 16 in the Champions League, despite finishing in the top two of the Premier League in each of the last four seasons.
"It's really important and everything has been so bright and so good for us so far," Kompany told reporters.
"It's the same as what people have been saying for the last three or four years - as long as we don't perform and show our quality in the Champions League, as we have in the Premier League, there will always be something left behind that leaves us unsatisfied.
"It's a really important game for us. We've been looking forward to the start of the competition since the disappointing game in Barcelona."
Manchester City kick off their Champions League campaign against Juventus on Tuesday evening.
