Madrid - Holders Real Madrid will need to maintain their intensity for the whole of next week's return leg if they are to get past Atletico Madrid into the Champions League semi-finals, coach Carlo Ancelotti said on Tuesday.
Real dominated their city rivals in the first half of Tuesday's quarter-final, first leg at Atletico's Calderon stadium but were unable to convert a host of chances.
Spanish champions Atletico then fought back after halftime, with both sides having chances to break the deadlock before the repeat of last season's final ended 0-0.