The stand-in coach at Camp Nou believes his side must have a positive attitude and says Saturday's Clasico remains "an important match" despite the gap in La Liga.
Despite Tuesday's 3-1 humbling at the hands of Los Blancos at Camp Nou in the Copa del Rey, Roura says everything is well with his squad.
"Our morale has to be good, because our attitude is unbeatable and we will win again," Roura told reporters.
Looking ahead to Saturday's latest Clasico, which is a league match instead of a cup battle, Roura believes it is a big clash that could have a bearing on the title race despite Barcelona's 12-point edge over Atletico Madrid and 16-point lead over Real Madrid through 25 games.
"It's an important game and we have played them [Madrid] a lot," Roura said. "The league title is the ultimate and to get a positive result would be a big step forward."
When looking back at the defeats to Real Madrid and AC Milan, Roura was honest about his side's shortcomings.
"We have analyzed the problems and we are quite clear," Roura said. "[But] many of these issues are because we were playing against a very strong team.
"When we play Madrid [on Saturday], we will try to improve what we did wrong against them before."
Following the final Clasico of the Liga season, Barcelona will start turning its attention to facing Milan in the Champions League last-16 second leg at Camp Nou on March 12, looking to overturn a 2-0 deficit.