Barcelona will take a slender advantage to Camp Nou after they beat Real Madrid 1-0 in their Copa del Rey semi-final first leg at the Santiago Bernabeu on Thursday.

An Eder Militao own goal was all that separated the two Spanish giants, with Carlo Ancelotti's men having a lot of the ball but unable to craft much in the way of chances.

Militao's own goal was only the fourth this century in a Clasico, three of which have favoured Barca after Ivan Helguera's in May 2002 and Raphael Varane's in February 2019.

Madrid may consider themselves fortunate not to lose by more, however, with Ansu Fati inadvertently denying team-mate Franck Kessie a certain goal in a second half largely dominated by the hosts.

Karim Benzema had the ball in the net early on when he chested down a cross from Vinicius Junior and volleyed home, only to be flagged offside.

Despite Madrid dominating early on, it was Barcelona who took the lead in the 26th minute.

Ferran Torres played in Kessie, whose shot went in off Militao after Thibaut Courtois had initially saved from the Barca midfielder.

Vinicius saw an effort blocked by Ronald Araujo early in the second half, while the visitors should have doubled their lead 18 minutes from time.

Kessie met Torres' cut-back but saw his goal-bound shot deflected wide by substitute Fati with Courtois stranded.

Nevertheless, Xavi's men held on despite Madrid's desperate late onslaught.

What does it mean? Madrid fail to out-Barca Barca

There has been plenty of talk recently about how Barcelona under Xavi do not really play the way the cultured midfielder and his team-mates did back in the day.

While still easy on the eye at times, the Blaugrana are more direct and seemingly less concerned about having as much possession as possible, as was the case when their head coach was strolling around the park.

That was evident here as Madrid had 64.7 per cent of the ball, yet they could not get past an organised Barca defence that sat in and worked hard for their one-goal victory.

Busquets becomes Clasico's most prominent player

Sergio Busquets made his 46th appearance in El Clasico in all competitions, surpassing Lionel Messi and Sergio Ramos (45 each) as the player with the most appearances in games between Madrid and Barca.

The 34-year-old may have been a little sloppier in possession than he usually is, but he mopped up to good effect, his 10 recoveries more than any other Barca player.

Wasteful Madrid unable to test Marc-Andre ter Stegen

Nine days after being as ruthless as could be at Anfield, scoring five goals from nine shots and six on target against Liverpool in the Champions League, Madrid found the other extreme here.

They had 13 shots in the game, not only failing to score, but unable to even hit the target with any of them.

What's next?

These two will do it all over again at Camp Nou on April 5 in the second leg. But first, it is back to LaLiga action as Madrid travel to Real Betis on Sunday, while Barca host Valencia the same day.