Luiz Felipe Scolari's men defeated Paulo Bento's side 3-1 in a friendly on Tuesday, with the Barcelona attacker among the scorers.
Postiga was impressed with how the World Cup host connected as a unit in the Massachusetts clash and argued that Neymar is just one part of the team's brilliance.
“Neymar played very well tonight and is a fantastic player, but it's not just Neymar, this Brazil team is fantastic,” Positga told reporters.
Portugal had gone a goal up through Raul Meireles but Postiga feels that they missed the influence of Cristiano Ronaldo.
“The start of the game was good. We scored an early goal and we played very well," he continued. "After that it was a difficult game. Brazil played with intensity and we couldn't handle it.
“Ronaldo is an important player for Portugal. He can make the difference in any game, but it’s important we focus on the players that are here."
Finally, Postiga spoke glowingly about the atmosphere at the stadium, saying it was great to see the American public flocking to see the game.
“It was fantastic because the stadium was full. It’s an important game for the people living in the USA, and we’re happy to play this game for the people," he concluded.