The Dutch playmaker urged his teammates not to focus on just the Real Madrid forward as he hopes his side can get the result needed to book a ticket to the quarterfinals.
Bert van Marwijk's men have lost their opening two matches in Group B, going down 1-0 to Denmark in their opener and losing 2-1 to Germany in the following fixture.
The Oranje now have to beat Portugal on Sunday and hope that Joachim Low's side defeats the Danes in the other Group B fixture to ensure passage to the quarterfinals. Seleccao talisman and captain Ronaldo is likely to be the main threat to Dutch hopes, but Sneijder believes it will be a mistake to focus on just one man.
"Portugal is not just Cristiano Ronaldo," he told Goal.com in an exclusive interview. "The proof is that he hasn't scored a goal in the Euros yet, and I hope it stays that way on Sunday.
"If we look at what we have done throughout this year, we can beat Portugal and win well, but that will depend on how we approach the match in the opening minutes. If we score early, anything can happen.
"The situation is beyond difficult, but not impossible. Now we are focused solely on Portugal and on scoring goals, and we will see what happens in the other match."
Netherlands entered the championship as one of the tournament favorites and Sneijder stated that he can sympathize with the fans after his side lost its first two matches, while also admitting that the predicament has taken the squad by surprise.
"Nobody thought during the pre-tournament camp that we would have no points after the first two games of the Euros. That was totally unexpected for us," Sneijder conceded. "The first defeat against Denmark knocked the wind out of us because nobody could understand how we lost that match.
"I understand our fans are disappointed and we are even more so, because before the tournament we saw ourselves with sufficient strength to win it and now we could go out in the first round."
The Inter midfielder previously hit out at the "pathetic egos" in the Dutch camp after the loss against Denmark, but claimed that there is unity within the ranks ahead of Sunday's crunch clash.
"There are no problems in the Dutch camp and there's no crisis," Sneijder explained. "We all want to win and it's normal there are no happy faces, but we are professionals and we are only thinking about the team, about winning the three points and scoring goals against Portugal."
Netherlands take on Portugal at 2:45 p.m. ET in Kharkiv with Denmark's clash against Germany kicking off at the same time in Lviv.
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