Raya featured in the 2-1 friendly win.
He said, "It has been an incredible week, I have arrived, first call, first game, the truth is that it could not have been done in a better way.
"I am very happy to have made my debut and especially at home, because Barcelona is an incredible city and it has been a very special moment that will mark my entire personal and professional life, having all my family and friends supporting me.
"There are eight months left for the World Cup and I see myself ready to compete in a competition as big as that. We have a very good group, with incredible quality, as we showed against a team that is very hard to break. We were strong at the back and created enough chances to get the win."
Raya added: "I don't have that kind of relationship with David, nor have I played against him yet. Nothing happens. I wish him well. He is doing a season at United, there is no doubt."