The Foxes sit just a point off the Premier League relegation zone after 25 fixtures, with their misery only highlighted by their historic trophy-winning campaign last time out.
Their reward is a two-legged round of 16 tie against Sevilla, with a trip to Andalucia to kick off proceedings, and Ranieri is expecting a stronger showing from his players.
"Will we have the balls?" Ranieri asked the Daily Mail. "I want the matadors. I want the gladiators, I want the soldiers, I want my players.
"It could be the turning point, it could be everything. We can lose, it’s OK, nothing happens. But if we win, if we do a very good game, something inside could change. We need one match like this.
"We play without the pressure of the Premier League, we play light. For this reason I hope we can show our football. They are better than us, but we will fight."
Leicester's spiralling form in the Premier League has sparked uncertainty in regards to Ranieri's future, with the Foxes' 1-0 defeat at 10-man Millwall in the FA Cup further adding to the pressure on the Italian.
The club have publicly backed their manager, however, with last season's miraculous triumph earning him the right to at least complete the current campaign.
Asked whether he had earned the right to decide when he leaves, he replied: "I could have left last season. Nobody could have said anything — I won the title.
"But I wanted to stay because I knew it was a difficult year. I came here to build something good for Leicester and I’ll keep going. I’ve forgotten the title.
"We know we all have to work harder. Do that and chances will come. You will always get criticism. I blank it out and focus on what’s important, which is getting away from the situation we are in."