The assistant coach, who is deputising for boss Tito Vilanova while he recovers from cancer treatment, oversaw the Catalans' late 4-2 win against Malaga on Thursday to set up a Clasico.
And while he acknowledges that the derby may pose his team a distraction, Roura is nonetheless keen to bounce back in the league against the Basques after last weekend's maiden defeat to Real Sociedad.
"We've just had a good game [against Malaga] and on Wednesday we have an important game - but before that is Osasuna," he said at a press conference on Saturday.
"We can’t let our guard down and I’m sure that won’t happen. We must carry on with the same intensity and keep on winning.
"We have to take each game as it comes regardless of how important the Real Madrid match is. We're going to concentrate exclusively on Osasuna."
Despite languishing in the relegation places, Osasuna have the fourth best defensive record in the Spanish top flight, and Roura expects Los Rojillos to make life difficult for Barcelona.
"They're solid defensively," he added, "We've just had a tough midweek match and I don't think it'll be an easy game.
"But all in all, I think we’re ready to compete at the highest level."
Victor Valdes recently announced that he would be departing Camp Nou once his contract expires in 2014 - a decision which was met with some derision from the club's supporters - but Roura believes the goalkeeper will receive a good reception on Sunday.
He added: "Valdes is our goalkeeper and I expect him to get a warm and respectful reception, as he's always had."