Portugal struggled to break down Iceland as they drew their opening fixture 1-1 and found life difficult against Austria at the Parc des Princes on Saturday, failing to find the net despite having 23 shots on goal.
Cristiano Ronaldo failed to convert from the penalty spot with 11 minutes remaining on his record-breaking 128th cap for the Selecao, while Nani struck the upright in the first half.
The Fenerbahce forward admitted Portugal's display was not good enough, but expects them to come good in their final Group F match against Hungary.
"We had to win, we gave it everything, we did everything right, but the ball did not go in, once again," said Nani.
"What can we say? We cannot excuse ourselves with 'the ball won't go in, the ball won't go in' – we had chances.
"The team played really well. Once again we showed that we can play good football. We were superior, we controlled the match against a strong team that also played excellent football.
"I think our moment will come, and it's right in the next match. There is no other way, it really has to happen."