Borja Iglesias scored for the 1-0 win, with Iago Aspas and Ilaix Moriba both being sent off for Celta.
Giraldez later said, "One of the things we had to improve or introduce into the team was having soul, being competitive when things aren't going well.
"Today we came out much stronger, I think the team is making many steps in that competitive aspect that is sometimes not measured and had not been entirely fair in some games with what we had done on the field.
"The two expulsions have been good for us to strengthen that part of the team. We are very happy with the effort of the players."
On the referee, Giraldez said: "He made his decisions. We have to respect that. There are things that don't quite fit with what we're told in talks about offside, small decisions and so on. I'm not going to go into the rest, it's up to everyone to judge. In my opinion, the more unnoticed the referees, like the goalkeepers, the better, and today he was the protagonist.
"I suppose because he saw it that way and we have to respect that. Something strange happened. There were two expulsions in a match between two combined teams and there were practically no fouls."