Xavi Hernandez admitted it would be hard to sleep after Real Madrid outclassed his Barcelona side in a 4-0 Copa del Rey at Camp Nou on Wednesday.

Los Blancos reached the final 4-1 on aggregate, knocking out the 31-time record Spanish cup winners after Vinicius Junior opened the scoring and Karim Benzema scored a hat-trick in the second half of the second leg.

Xavi had led Barcelona to victory over Madrid in the last three Clasicos, but Madrid stunned their rivals to set up a final against Osasuna on May 6.

"We're hurt today, yes. It will be hard to sleep, more so as the big Barca fan that I am," Xavi told reporters.

"I told the players (this could happen), we had chances but went in at 1-0. It's a shame because we competed well in the first half and that was our moment.

"In the second Madrid were better, sincerely, they were better physically, they pressed us high. There are no excuses."

Despite the painful defeat, Barcelona should still be able to clinch the Spanish title, holding a 12 point advantage on Real Madrid in second.

Barcelona also beat their rivals in the Spanish Super Cup final in January.

"If we win La Liga and the Super Cup it's a good season," added Xavi.

"There are 11 finals left, and we have to keep competing."