The Oranje are famous for playing a 4-3-3 but a 2-0 defeat to France in March prompted a change of thinking among the staff and players.
Van Gaal has since settled on a 5-3-2 system, and Robben says he is behind the new approach and dismissed fears it could compromise the team's attacking instincts.
He told De Telegraaf: "After the France match, I thought long and hard and talked it over with other players. We spent two hours discussing what was best for the team. The coach came up with the idea of playing 5-3-2 and I bought into it. We've always been on board with the Dutch school and intricate football and I believe our strengths still lie in positional play and going forward, but we mustn't be too open."
Reigning world and European champion Spain is the Netherlands' first Group B opponent of the World Cup on Friday and Robben believes the tactical shift could prove key.
"We were overrun by France and we knew we would have to be mindful of that against Spain, because otherwise we would have a problem," he said. "If we leave big gaps against Spain we will be in trouble. We mustn't give it away at the back and we have enough training days to ensure the team stay together as a unit."