The Brazilian came off the bench to score the only goal of the game as Los Blancos beat Real Valladolid on Wednesday night.
"We're happy with the win because it was a tough game," Vinicius told Movistar at full time.
"The first half was difficult, but the team changed in the second and we got control of the game.
"It was important to keep winning.
"We knew that if we kept a clean sheet, we're going to win for sure because we have lots of people that can score goals in attack.
"We'll improve as the season goes on."