Pablo Zabaleta claims the mood at Manchester City would be transformed instantly if they can shock Barcelona in midweek.
Gloom is descending at the Etihad Stadium as City look to be relinquishing their grip on the Barclays Premier League trophy.
Their hopes of rescuing the season with a prolonged Champions League run also seem unlikely as they head to Nou Camp on Wednesday trailing 2-1 after the first leg of their last-16 tie.
But Zabaleta, despite Saturday's morale-sapping loss at Burnley, retains belief and thinks the in-form La Liga giants can be taken down at their own ground.
The Argentina right-back said: "We are going to play against one of the best teams in the world. It's not going to be easy, but nothing is impossible in football.
"You have to be ready for these moments. Things can change on games like this.
"You just have to move on to the next game and try to win it. That's what football is.
"It's good that the game (comes after) just three days. We need to recover well, go to Barcelona and see what we can do. Hopefully we can do it."
City were completely outplayed in the first leg at Eastlands three weeks ago but somehow managed to limit the damage after two early Luis Suarez goals.
Joe Hart saved a late Lionel Messi penalty after Sergio Aguero pulled a goal back and Zabaleta sees reasons for optimism.
Last week Schalke gave Real Madrid a fright, winning 4-3 at the Bernabeu and only narrowly going out on aggregate, while Paris Saint-Germain stunned Chelsea.
Zabaleta said: "Mentally we must be very focused but if you look at the game Real Madrid played against Schalke and the same with Chelsea and PSG, it shows anything can happen in football.
"That's why we need to go to Barca with confidence with belief and try to do our best to win that game.
"We have played in this competition for four years. It's a competition we want to make progress in."
City have won just three of their last nine Premier League games to fall six points behind Chelsea, who have a game in hand.
That has brought criticism and increased pressure on manager Manuel Pellegrini.
Zabaleta said: "We need to look at ourselves, be self-critical. When things are going well everyone enjoys it but sometimes in football you try to do your best but you don't get results.
"This is not our best. "The only way we can improve is to work harder during the week. This is the best way to get results."
Source: PA
