Diego Simeone has called on the Atletico Madrid fans to contribute to a memorable night as they host Barcelona in the second leg of their quarter-final on Tuesday.
The tie is level at 1-1 as Neymar's equaliser cancelled out Diego Costa's incredible strike for Atletico to ensure there has still not been a winner in four meetings between the sides so far this season.
"I know a lot about the club and the fans need to understand what is important for us, especially at this stage in the season having played so many games," Simeone said.
"The atmosphere was rocking [at the weekend] and that gives you more energy and strength to compete. When people ask 'why do we support Atleti,' it is for this. We are passionate, humble, work hard and if we have to suffer, we suffer."
Both Simeone and Barcelonaa boss Gerardo Martino lamented how much the first leg had taken out of their respective squads as Barca also struggled to a 3-1 win over bottom side Real Betis on Saturday.
Barcelona will also be affected by key injuries to Victor Valdes and Gerard Pique as they travel to the Spanish capital.
However, Marc Bartra - who will deputise for Pique at the heart of the Barca defence - believes they have already shown their ability to overcome injuries this season having lost Lionel Messi for two months earlier in the campaign.
"We have had bad luck with injuries, but this group has shown that it can overcome delicate situations. We need to do that again and do our best," he told the club's website.
"I am very positive about this match, we are going to the Calderon full of hope that we can go through."
Atletico could also be without top scorer Diego as he limped off with a hamstring injury after just half an hour of the first leg last week.