Erick Marcus had the hosts ahead before two goals in a minute from Inaki Williams and Nico Serrano in the second-half sealed the win for Athletic.
Afterwards, Valverde admits Ludogorets made it a tough night.
Performance:
"It was a very difficult game, they played bravely, they played hard, we had a hard time getting into the game and taking the field. Once they have scored the goal they have closed and it has cost us more, the match has been advanced and we have been able to score."
Take advantage of the moments:
“The teams accuse the blows they give us, the best time to attack the rival is when they're open. Unai has made a brilliant driving for Nico to score in the end. It cost us, but we are happy.”
The importance of changes:
“Changes are always decisive, the game is what it is, when we make changes the players try to mean themselves and above all that the team can improve. They have entered well because it gives them a lot of confidence and it is very good to have players who can be reactive.”
The table:
“As we have no experience in this competition, we may already be there, but since it is the first experience we have to go day by day. We have four other games with important matches and we will see that the competition holds us."
Nico Serrano:
“He deserves it, he is working well, he was having few options, but he has also had an injury that made him join later. That is what we hope will be decisive as it has been today.”
Ander Herrera:
“He has a great impulse, he is a player who also has faith in his arrival because he surprises and we're looking for him. In Mallorca he was close to the goal, against Betis too, today again. It is good that you find those situations and the prize will come. He is a player who always enters games well. The important thing is to have energy.”
Iñaki Williams:
“He is confident and a player who has quality, against Espanyol he had a similar situation. We have confidence in that position."