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BARCELONA, Dec 18 (Reuters) - There was no dream ending for Olimpic de Xativa after an efficient performance from a second-string Real Madrid secured a 2-0 win at the Bernabeu which sent them through to the King's Cup last 16 on Wednesday.
A 0-0 home draw had built up Olimpic's hopes of an unlikely upset but Asier Illarramendi eased Real's concerns with the opening goal after 16 minutes and midway through the first half Angel Di Maria converted a penalty.
Gareth Bale was among the injured players and Cristiano Ronaldo was suspended for a game in which Real coach Carlo Ancelotti kept faith with his second string who had disappointed in the first leg.
Real reached the last 16 along with Atletico Madrid, who beat their Madrid rivals in last season's final, and won 2-1 against Sant Andreu earlier on Wednesday to advance.
Barcelona made short work of Cartagena with a 3-0 victory on Tuesday to qualify 7-1 on aggregate.
"We tried to get more goals but the important thing is that we played well and we respected the opposition," Real defender Pepe told reporters.
"We had a good rhythm to our play, the team is united and we are working hard."
Olimpic made the 400km journey from south of Valencia by coach looking to repeat the feats of lower league sides Alcorcon and Real Union who have knocked Real out of the Cup in recent seasons.
The visitors were willing to take the game to Real and attacked down the wings through Alejandro Belda and Denis Najera but they lacked creativity and a cutting edge.
After a slow start, Real began to find their feet and Illarramendi put them in front, finishing clinically from a pass by Jese Rodriguez.
A header from Alvaro Morata was handled by Enrique Alcazar inside the area and Di Maria extended Real's lead as he converted the penalty.
Real controlled the game after the break but despite their possession they struggled to create further chances as Olimpic closed them down well.
"It has been a fantastic experience from the moment the tie was announced. We've had the chance to play in the Bernabeu and although we conceded goals in the first half we have given a good account of ourselves," Olimpic midfielder Eduardo Rifaterra said.
A stoppage-time goal from Tobias Alderweireld gave Atletico Madrid victory over lower league Sant Andreu.
After their resounding 4-0 first-leg win coach Diego Simeone used his squad players to finish off the contest at the Calderon but it was the third division side who scored first through Alberto Corroza.
The defender was quickest to react when an Adrian Mourino free kick was turned on to the post by Daniel Aranzubia and he slotted the ball home after 14 minutes.
Atletico had a golden chance to equalise when Adrian Lopez was fouled by keeper Jose Miguel Morales for a penalty but Adrian blazed his spot-kick over the bar.
Adrian, however, made amends 12 minutes from the end when he crossed for Hector Hernandez to score.
In the dying moments, Atletico, who are joint leaders of La Liga with Barcelona, got the winner through a Alderweireld header from a Gabi Fernandez free kick.
Real Sociedad also reached the next round with a 4-0 win over lower league Algeciras to seal a 5-1 aggregate victory.
Third division Racing Santander pulled off a shock as they beat Sevilla 2-0 away to go through 2-1 on aggregate. (Reporting by Tim hanlon, editing by Ed Osmond)