Athletic Bilbao coach Ernesto Valverde insists the Copa del Rey semifinal is wide open after their first-leg win at Atletico Madrid.

Alex Berenguer's penalty sees Athletic take a 1-0 lead back to Bilbao.

Valverde said: "I expected a match of this tension, it was noticeable in each duel. In the first half we were better, hovering around the area, and that's where the goal came from.

"Then it was difficult for us to settle down a bit and we also had the option of scoring the second goal. We had to do a good defensive job.

"I don't think it was the best of the season. There have been games in which we have dominated more, but we had Atlético in front of us and if you don't dominate certain situations, they will put you behind. This is just the first part of a double game and we still have San Mamés. We will have to suffer to get through.

"I see it absolutely open. We recently beat Atlético in San Mamés, but we have lost many times against them. It is open for either of us. In San Mamés there will be an atmosphere like that of the Metropolitano.

"Everything is to be decided and what it will be about is being above the tension of the game, playing with head and heart. Both teams will go for everything."