Thibaut Courtois said Real Madrid "dominated" and were "really unlucky" to lose 1-0 to Barcelona in their Copa del Rey semifinal first leg on Thursday.

An own goal from Eder Militao in the first half -- the ball rebounding off the defender into the net, after goalkeeper Courtois had saved Franck Kessie's shot -- was enough to give Barca the win at the Santiago Bernabeu, with the second leg to come at Camp Nou on April 5.

"We dominated the game today," Courtois told TVE after the match. "[Barcelona] were quite defensive. We were really unlucky to concede the goal. They won the ball, I saved [the shot] and it rebounded off Militao and went in. They were leading when they didn't deserve to.

"It was hard for us to create chances. It's difficult, we played a good game, we were in control, but we didn't get the chances. They defended well."

Barcelona are chasing a domestic league and Cup double, while Madrid are looking to cut into the leaders seven-point lead at the top of LaLiga and turn around the Copa semifinal.

Despite controlling possession and forcing Barca to defend, Madrid were unable to muster a shot on target themselves, but coach Carlo Ancelotti praised his team's performance.

"It was a good game. We planned for an intense game and we got it," Ancelotti said in his postmatch news conference. "We pressed them a lot. We could have been better in the final third, but it was difficult, there wasn't much space.

"We went outside with a lot of crosses, but at the back they're very strong in the air. It was the game we wanted to play, obviously not the result, but it gives us confidence. We simply have to repeat this game in Barcelona.

"We started and ended the game well. [The goal] was an individual mistake, a bad pass, they hit us on the counter and scored with a rebound. It affected the team a bit.

"We're satisfied with the game. You can't always control a team like Barcelona. Defensively, pressing high, this was one of Madrid's best games."

Madrid travel to Real Betis in LaLiga on Sunday and host Espanyol the following weekend, before their Champions League round-of-16 second leg game with Liverpool at the Bernabeu.

In addition to the Copa del Rey second leg in April, Madrid also travel to the Camp Nou for a LaLiga match on March 19.