Luis Enrique said Barcelona are capable of scoring six goals against Paris Saint-Germain on Wednesday as the La Liga leaders target a historic European turnaround.
Barca were beaten 4-0 in Paris in the first leg, a result which no side has ever recovered from in the Champions League.
However, with an improvement in results in recent weeks, capped off with an impressive 5-0 win over Celta Vigo on Saturday, the Catalan club believe they're capable of becoming the first side to achieve the feat.
"We are only halfway through the tie," Luis Enrique said in a news conference on Tuesday ahead of the return leg at Camp Nou.
"If a team can score four against us, we can score six. That doesn't mean we have to score a certain amount by a certain point, but we have nothing to lose and a lot to gain."
Luis Enrique has switched to a 3-4-3 formation since that heavy loss in the French capital, with three consecutive wins following the change.
Boosted by the improvements, the Barca boss added that "anything can happen in 95 minutes" and emphasised his belief that his side will find their way back into the tie -- even if they ultimately come up short.
"While there's life there's hope," he continued. "Many things have happened between the two games.
"We go into the game in good circumstances having improved our performances. We have to be optimistic and we are.
"I am convinced that at some moment we will be close to qualifying, although I don't want to say we will achieve it. And when we're close, our morale will keep on growing and [PSG's] may decrease."
There are doubts over whether Barca will stick with their new formation and also regarding whether Andres Iniesta will start, having been on the bench for the last two matches, but there were no clues from Luis Enrique.
"I don't give clues and especially not for this game," he said. "All 25 players can play all the systems -- and we can play an infinite number of systems."
With Luis Enrique due to leave Barca in the summer, he was asked if being knocked out of the Champions League would signify a failure.
"Ask me after the game," he responded. "It's not over until it's over."
Luis Suarez echoed the comments made by his manager.
"No one wants to turn the tie around more than us, but we need to be calm," he said. "We want to go down in history."