Barcelona need to be more efficient in front of goal and iron out defensive lapses if they are to beat Real Madrid in the Copa del Rey semi-final, insist assistant coach Jordi Roura and midfielder Cesc Fabregas.
Holders Barca have a slight advantage for tonight's semi-final second leg at the Nou Camp after securing a 1-1 draw at the Bernabeu in the first leg.
However, they showed a lack of ideas in attack in losing 2-0 at an ultra-defensive AC Milan in last week's Champions League last 16 first leg and again appeared vulnerable at the back in coming from a goal down to rescue a 2-1 La Liga win at home to Sevilla on Saturday.
It was the 11th match in a row in all competitions in which the runaway La Liga leaders failed to keep a clean sheet.
"We have seen that some of the goals have been conceded through our own fault and we will try to correct that," Roura, who is standing in for Tito Vilanova, said.
With Cristiano Ronaldo (above) firing on all cylinders, a tight defence is particularly important for Barca. Before the first leg, the Portuguese had scored at least once in his last six Clasicos and headed the goal that gave Real a 1-0 victory over their arch rivals in the 2011 Cup final.
Fabregas, who netted Barca's goal in the first tie before Raphael Varane grabbed a late equaliser, said he and his team-mates will need to be as ruthless as Real in taking their chances.
"We have to be as effective as possible in the return game because they are," he said. "We have to be on good form in front of goal if we want to get through.
"Madrid are very dangerous and to qualify for the final we have to play the best football we are capable of."
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