The win secured the club's fourth Copa del Rey title and their first since 2020, and their head coach said the moment marked the start of something bigger.
Speaking after Pablo Marin converted the decisive penalty, Matarazzo said the emotion only fully hit once the ball hit the net.
"It was that moment when we realised that it was real, that we had achieved it," Matarazzo said. "Until you're done, you don't have the feeling that it happened. It's incredible. Thank you to all the fans for their support. During the last few days and today it has been an incredible experience for the team and we are very grateful for today's support."
The match itself was a tense, hard-fought contest, with both sides cancelling each other out over 120 minutes before penalties decided the outcome. Matarazzo admitted his side had to dig deep, particularly in the second half.
"I don't want to be too tactical," he said. "It was important for us to control the game as best we could. Not to take risks. We did a good job defensively. We had to suffer in the second half, but this is the character of the team."
He also singled out goalkeeper Unai Marrero, who played a key role in the shootout by saving two penalties.
"(Marrero) played a perfect game," Matarazzo said. "I love the energy he has and that he overflows with the fans at certain moments. It was no coincidence that he stopped the two penalties."
Looking ahead, Matarazzo believes this victory could be the foundation for more success at Real Sociedad.
"We have fantastic players, they did incredible on the pitch against a great opponent," he said. "I'm very happy. And I feel that this is just the beginning."
