Barcelona were soundly beaten by Juventus in the first-leg of their quarter-final clash, with a brace from Paulo Dybala as well as a goal from Giorgio Chiellini giving the Italians a 3-0 win in Turin.
That means Barcelona will have to score at least three goals at the Nou Camp if they are to win the tie, just weeks after they thrashed PSG 6-1 at home to overturn a four-goal comeback.
And Neymar is confident Barcelona can replicate the feat when they welcome Massimiliano Allegri's team to the Nou Camp on Wednesday.
“We have to believe we can do it,” Neymar said to Canal Esporte Interativo. “We can be behind any team, but at Barcelona it's always the same: We can do it.
“If everything goes well, another comeback will happen, I believe in the team and in our potential.
“Everything is lost, so we have nothing to lose and everything to win."
Neymar also sought to praise Juventus ahead of the second-leg, acknowledging that the Serie A champions are a strong team.
“Juventus are a great team, very well structured, so it will be difficult to have to turn the tie,” he added.
“It is the same as the situation against the PSG. We have a one percent chance of qualifying and the remaining 99 per cent is work, faith and, god willing, goals. They are going to arrive.”
Barcelona’s chances of winning the tie will surely be boosted by the news that Juventus could be without forward Paulo Dybala, the hero of the first-leg in Turin.
The Argentina international limped off early in the second half of Juve's 2-0 win at Pescara with an ankle injury.
“He's taken a knock and twisted it a little but there's still four days, we have to be optimistic,” Juventus coach Massimiliano Allegri said.
Allegri also promised that Juventus wouldn't fall into the same trap of sitting back against Barcelona on Wednesday — an approach that doomed PSG.
“Our aim is not to score just one goal, but to get at least two,” Allegri said.
Barcelona will meanwhile get Sergio Busquets back after he was suspended from the first leg.