Celtic began plotting the football "miracle" they need to reach the Champions League quarter-finals after surveying the damage of their 3-0 home defeat by Juventus.
Neil Lennon's side were on the end of a clinical and ruthless display from the Italian champions, who withstood some sustained pressure, especially in the first half, to all but seal their place in the last eight.
But Celtic right-back Mikael Lustig refused to give up all hope of upsetting the odds in Turin on March 6.
The Swede told uefa.com: "It's almost mission impossible but miracles have happened in football before.
"You never know - a penalty, a red card then maybe we're back in the game, but it's really tough now."
Celtic midfielder Kris Commons also held on to some optimism despite his bitter disappointment at the heavy defeat.
Commons said: "We won't be going over there thinking the tie is over. We've got a good set of players and our coach won't let us believe this tie is over.
"If we have a really good night and they play poorly, you get a couple of early goals you just never know, so we'll be going over trying to stamp our authority on the game and get an early goal - that would be ideal for us."
Commons came close on a number of occasions during a first half largely dominated by Celtic, even before Alessandro Matri capitalised on a misjudgement by Efe Ambrose to net in the third minute.
Victor Wanyama and Ambrose both missed excellent headed chances and Celtic paid the price in the final 15 minutes.
Claudio Marchisio grabbed a second following a slick counter-attack and Mirko Vucinic finished after another mistake by Ambrose, who had only returned to Glasgow on the morning of the game after playing for Nigerian in their African nations Cup win on Sunday night.
And Celtic can rightly take some encouragement from their general play as they plot an unlikely comeback.
Commons said: "We had some good build-up play and possession which got us in good areas.
"The keeper made some good saves but you get paid for what happens in both boxes and we couldn't quite get a goal and conceded three sloppy goals which near enough ends our run in the competition.
"It's hard to put into words when those kind of mistakes are happening at this level.
"It's frustrating but it was one of those games where individual mistakes cost us the game.