Barca are overwhelming favourites to claim all three points from the Liga clash having won their last eight games against Paco Jemez's side, who they have outscored 34-1 in those meetings.
But Luis Enrique explained: "Every team presents their own difficulties. It's a nice game, we like it because it's going to be a challenge and we're ready.
"He's [Jemez] a coach with a great offensive spirit. I really like his way of coaching. There are very few teams that have the ambition and personality of Rayo Vallecano.
"Some teams play very defensively and some teams attack. If we don't create a lot of pressure, it's going to be difficult for us.
"If we are able to create scoring chances, we usually win."
The hosts will be without midfielder Sergio Busquets after he suffered ankle ligament damage in Wednesday's Copa del Rey success over Villarreal.
"We have certain options because of the injury to Busquets," Luis Enrique added. "I don't want to give hints as to what we're going to do. I have several options to take Busquets' place.
"As we get closer to the end of the season, the situations are more difficult and there's pressure. The most important thing is not to become distracted."
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