Alfonso Gonzalez struck before halftime for the only goal of the game.
Giraldez later said: "We know it wasn't our best match. We were very good competitively, but not in terms of football. We played better in the first half; in the second, we lacked energy.
“They took a huge risk playing man-to-man the entire game, they defended very well, were very aggressive, and played a very good match. We're in that dynamic where no matter the context we have in the game, we're capable of competing.
"The team pulls together, each helping the other, and I think that was the key, even though we were in a low block for too long today. It's impossible to go an entire season without having difficult moments in those areas of the pitch, and today it was necessary.”
He also said: “I think it's incredible to have gotten 52 points. Not even the most optimistic of us expected that, and now we have to try to get six more in these two games. It shows how everyone has done so well this year, not just those of us on the pitch.”
Sitting in seventh place, Giraldez also said of Europe: “Obviously, we're closer to it, but we have to seal it, and we have to win these two remaining games.
"We've already seen how difficult it is to win every game and every inch of the pitch at this point in the season.”