Barcelona coach Tito Vilanova has work to do on his defence before the visit of Valencia this weekend after errors from Gerard Pique and Javier Mascherano handed Real Madrid the Spanish Super Cup.
Jose Mourinho's men scored twice in the first 19 minutes at the Bernabeu on Wednesday, capitalising on mistakes from both central defenders to score and win 2-1 on the night and deal Vilanova his first defeat since replacing Pep Guardiola.
In last week's first leg, it was goalkeeper Victor Valdes who committed a howler allowing Angel Di Maria to grab a late goal for Real that effectively gifted them the first trophy of the season as they won on the away goals rule after a 4-4 aggregate draw.
Barca, who host Valencia on Sunday (20:30 BST), top La Liga with two wins from two but have shown some lapses in concentration at the back in their opening games.
"There are things we need to correct," Vilanova told reporters after the loss, preferring to focus on the way his side reacted to the goals and Adriano's 29th-minute red card to come back into the game with Lionel Messi's free-kick.
Barca and Spain defender Pique told reporters: "We should have done better at the start of the game, but to play here with 10 men as we did deserves respect."
Barca captain Carles Puyol sat out Wednesday's game as a precaution after fracturing a cheekbone against Osasuna last weekend, but could return wearing a face mask to tighten up the backline.
The Catalans also have a slight doubt over full-back Dani Alves who was forced to drop out of the second leg just before kickoff after suffering a muscle twinge in the warm up.
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