Pepe's red card proved to be costly as Paulo Bento's side were hammered 4-0 by Germany in their Group G opener in Salvador on Monday.
Portugal have no margin for error when they face the USA at Arena Amazonia in Manaus after Jurgen Klinsmann's side beat Ghana in their first game of the tournament.
Captain Cristiano Ronaldo has been suffering with a knee problem, but he will be expected to provide the inspiration for a Portugal side who know a defeat would end their hopes of progressing to the last 16.
Meireles is braced for a tough test against Klinsmann’s side, but believes Ronaldo and his team-mates are more than capable of securing three precious points.
The midfielder said: "I think it's normal, we have the best player in the world and people talk about him. We are used to it and it makes us feel very proud that people pay so much attention to him.
"We all feel very well, we know we have a difficult game ahead of us and we are prepared to play well.
"Cristiano played the last game, he's training every day with all of us, so I think Cristiano is fit to play. That's all I can say."
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