Coach Fernando Santos blamed a lack of pace and a failure to stay calm in the frantic final minutes for Portugal's inability to beat rank outsiders Iceland in their Euro 2016 opener on Tuesday.
With the Group F favourites 1-0 up thanks to a 31st-minute goal from Nani, dominating possession and generating a steady stream of chances, Iceland's second-half equaliser from Birkir Bjarnason came against the run of play.
"After we started having the ball and we moved on top we had many shots on goal," Santos told reporters after the 1-1 draw. "We only scored once. We could have and should have scored more," added the coach after sending on Eder, Renato Sanches and Ricardo Quaresma as late substitutes in a bid to snatch the three points."
"I think we are to blame for not scoring and I think in the final 10 minutes we were a bit anxious and we should have been more patient. We should have tried to score with cooler heads."
"Santos said he asked his team at halftime for more speed and intensity. We should have been pacier and we didn't define our crosses well enough," he explained.
It was a day of surprises in the group following Hungary's 2-0 upset of Austria earlier. "Everyone expected Austria to win and Portugal to win. I said this was a complicated group and things sometimes don't go off as planned," said Santos. "I think anything can happen (now)."
Portugal boast a fine record in the European Championship, having finished runners-up in 2004 and made the last eight in every competition since 1996.
"The first match is always complicated but the team is confident," said Santos. "We know what we want and I absolutely believe we'll bounce back to play two great matches."
Portugal next meet Austria in Paris on Saturday.
