Portugal's captain Luis Figo warned the hosts are gathering momentum after victory over Spain put them through to the quarter finals.
Figo said: "We're improving with every game and we showed the country they can look forward to better things."
"When the last game decides everything and you're playing at home the pressure upon you is high.
"But in general terms we did a great job and let's see what we can do in the quarter finals."
Portugal's campaign began in stuttering style with a defeat to group A runners-up Greece, and Figo admitted: "The first game wasn't easy for us.
"It was the opening game and there was a lot of pressure on us and all the players were worried about that pressure."
Figo's view was echoed by Portugal coach Luis Felipe Scolari who said: "We were bad in the first game against Greece and so we had to bet everything on the other matches.
"Fortunately, we won and we're happy. I want to send
congratulations to the public, which weren't the 12th player,
but the 13th and the 14th.
"Without them we wouldn't have had all this force to
fight to qualify.
"I only want to go ahead with the players.They did it,
they passed to the next stage, now nobody knows what is going
As Group A winners, Portugal could face either France or England in the last eight.
Scolari said: "As to who I would like to play, I don't care, it doesn't matter.
"I don't know really, once you get into the knockout stage it is
a lottery," said Scolari, who guided his native Brazil to victory in
the 2002 World Cup.