MADRID: Lionel Messi and Luis Suarez thrived again, leaving Barcelona closer to its fifth straight Copa del Rey final.

Suarez scored a second-half winner off a cross by Messi as Barcelona defeated Valencia 1-0 in the first leg of the semifinals on Thursday.

"They had a good plan (defensively)," Barcelona coach Ernesto Valverde said. "It was the team that best defended against us."

The three-time defending champion had difficulty getting past the Valencia defense at Camp Nou Stadium until Messi came through with a great play midway through the second half.

"Every time Messi gets the ball you expect something to happen," Valverde said. "It's a spectacle to watch him. In one improbable play he found a way to make the cross and we scored."

Messi controlled the ball inside the area and calmly carried it toward the end line, attracting three Valencia defenders. As they converged, he sent the ball all the way across the area to Suarez, who was free to score with a firm diving header.

"It's the smallest advantage," Suarez said. "There is still a lot of football to be played. Valencia is always strong, especially in a Copa semifinal."

It was a much better result for Valencia compared to the last time it faced Barcelona in the Copa semis two years ago, when it lost the first leg 7-0 at Camp Nou.

"We knew it was going to be difficult to play here against the best team in the world," Valencia defender Gabriel Paulista said. "We defended well."

Suarez has been enjoying an impressive scoring streak, having found the net 13 times in his last 11 matches. The Uruguay striker has scored in all but one of the 11 matches.

He and Messi have combined to each score in seven of Barcelona's last eight matches.

The second leg is next week at Mestalla Stadium.

"It wasn't a good result, it leaves us in a difficult situation, but the series is still open," Valencia coach Marcelino Garcia Toral said. "It may look impossible but we will go for it."

Valencia is trying to win its eighth Copa title, and the first since 2008.

Barcelona has a record 29 titles.

Five-time champion Sevilla drew at Leganes 1-1 in the first leg of the other semifinal on Wednesday. The return match is next week in Seville.

The Copa final is on April 21.