Iker Casillas acknowledges “Juventus are favourites” against Porto but “bravery can overcome individual ability”.
The Portuguese side face the Bianconeri on Wednesday in the Champions League Last 16, and the legendary goalkeeper believes they can progress.
“Playing so many important games in a prestigious competition like the Champions League, I have experience to call upon and I'm thankful for that,” Casillas told UEFA’s official website.
“I hope the other players can feel more confident because of that. Of course we're facing a very tough tie; we know Juve are the favourites, but sometimes excitement, desire, effort and bravery can overcome individual ability.
“Now we have to be realistic: we're a good team and we're gradually progressing with the help of our younger players.
“Now we're facing an opponent who's been at a high level for a long time, playing semi-finals, a final, quarter-finals.
“However, in the world of football, anything can happen. Six or seven months ago, we were in a play-off against Roma…”
The match is being billed as a battle of the goalkeepers, with Gianluigi Buffon and Casillas two of the most highly-regarded ‘keepers in history.
Between them, the pair have 334 international caps, 12 League titles and two World Cups, though the Italian is yet to lift the Champions League.
“I am lucky enough to be three years younger than Gigi,” Casillas said.
“I was 14 when I started and he was 18; I was able to see and appreciate his style and personality. As I grew up, I looked up to him and then we evolved together and we've had similar careers.
“We've both won a lot and we've often played against each other. I think Italian football won't have another goalkeeper like him.
“In Europe and around the world, he's considered one of the best of all time. Ours is a healthy, positive rivalry: we really appreciate each other and playing against him is always a pleasure.
“He is a player who is known and admired all over the world and he is part of the history of this game.”