Takefusa Kubo struck the only goal of the game as La Real won 1-0.
Imanol said afterwards: “I am very happy with the work of my players, against a great rival and a great coach, who, for one reason or another, was difficult to beat and today we did it.
"The game was going to be even and it was going to be decided in the penalty areas and that is what happened. A clearance by (Mikel) Oyarzabal and a play by Kubo allowed us to win the game.
"I agree with (Villarreal coach) Marcelino that the match was very even and that we had to be accurate in the box and we did. Last year we changed the trend at home a little, so that the fans would be more happy, and we will see if we are able to continue with that.
“It was neither the best game, nor the most brilliant of those we have played against Villarreal. I don't know if it was fair or unfair, other times they have won without deserving it because they got it right, today it was us.
"We fell for what they do, because they are the best team in transitions, the best, and we suffered, but despite that we managed to win.”
On Kubo, he added: “I am very clear about it and so is he. He knows that I am demanding of him, but it is because he can do it, because he has shown it. Today he entered the game very well, wanting to be the protagonist, as I always ask him to do. It is an action of wanting and then he has the innate talent to do what he has done.
"He has to have the ambition to do the numbers that I ask of him in terms of goals and assists, I know it is complicated, but he is showing that he is capable.”