Soares told FIFA TV that his teammates have the ability to beat Uruguay to the quarter-finals.
"We have a really close-knit team, we have worked pretty well together," the 26-year-old said. "We are already looking to the next game and that's what we're focused on right now.
"It was certainly a tricky group stage but the most important thing is that we are through, and now we have to look to the game against Uruguay.
"They're certainly great players, we too have great players, we have the best player in the world. So that's why we will study them, bearing in mind they are a strong side. However, we have our assets too and we will try to win the game."
Portugal finished second in Group B, level on points with Spain after one win and two draws.