Auxerre coach Jean Fernandez rates Real Madrid the biggest club in the world.
The French have already faced AC Milan, but Fernandez regards Real as the ultimate.
"Real Madrid are the biggest club in the world. San Siro was very emotional, but this will be something else," the Auxerre coach told Uefa.com.
"To see all these great players - [Cristiano] Ronaldo, [Gonzalo] Higuain, [Mesut] Oezil, [Angel] Di Maria - at Stade de l'Abbe-Deschamps will be a fantastic moment in my career as a manager.
"You mustn't have fear in football. After 20 minutes we were drawing with Milan, and after 40 minutes it was still even. Then we had an unmissable chance at the end of the first half. If we'd scored, maybe we would have come away with something from San Siro. That should give us confidence for the rest of the Champions League."