Barcelona boss Xavi hailed his side's defensive effort as a resolute rearguard kept Real Madrid at bay and came away from the Bernabeu with a 1-0 win to hand the Catalans the advantage in the first leg of the Copa del Rey semi-finals.
"We were extraordinary defending without the ball," said Xavi after the clasico win.
"Defending is part of the game, that's why the win is very important, it was a tremendous victory. Today we minimised Madrid."
Real had more possession and Xavi said that was not his gameplan.
"They pushed us into our own half a lot, they subdued us with the ball," he added.
"It's not the percentage of possession we're looking for. We need to play with the ball because otherwise we won't control games."
Barca ratings v Real Madrid
Barca resume their La Liga title push on Sunday when they host a Valencia side fighting for their lives at the bottom of the table.
Win over Real was secured without the services of top scorer Robert Lewandowski and key creators Pedri and Ousmane Dembele.
With few options in the squad for Xavi to rotate with, his first-choice players will have to battle tiredness against a rested Valencia.
Valencia earned their first victory under new coach Ruben Baraja last weekend against high-flying Real Sociedad and sit 18th, one point below safety.
Against Valencia and back at Camp Nou, Xavi's side will likely have more of the ball but Valencia boast plenty of attacking threat on the counter, including in-form winger Samuel Lino.
Barcelona hold a seven-point lead on second-placed Real Madrid going into the weekend.
Valencia midfielder Hugo Guillamon said his team were heading north aiming for three points.
"We will go there with clear ideas of what we have to do to get the win and the team will work hard this week to have a good game," Guillamon told Valencia's website.
"Barcelona have a lot of absentees but with the squad they have they can make changes and play at a very high level.
"It will be a tough game for us, but we will make it tough for them too."
Should Barcelona take three points it will confirm Xavi's side are back on track, but any other result will give Real Madrid the opportunity to further reduce their lead later Sunday against Real Betis.