Rafael Leao believes the hat-trick heroics of Goncalo Ramos in Portugal's 6-1 rout of Switzerland show what quality lurks in the squad's ranks as they chase a first World Cup triumph.

Even the president of Portugal, Marcelo Rebelo de Sousa, joined in the praise of Fernando Santos' team as they sped through to the quarter-finals in Qatar.

Ramos started Tuesday's game ahead of Cristiano Ronaldo, with the 21-year-old Benfica forward proving far from unnerved by that prospect, hitting the first, third and fifth goals of Portugal's handsome win.

It may mean Ramos keeps his place for the clash with surprise quarter-finalists Morocco, who upset Spain with a penalty shoot-out victory.

Leao came off the bench in the late stages and struck the team's exquisite sixth goal, staking his own claim for place in the side to tackle the Atlas Lions.

Asked about Ramos, Leao told Sport TV: "We have a lot of players of great quality, and he is another young man who showed a lot of quality.

"Today he had the opportunity to be in the starting line-up, he helped the team and we are very happy for him."

Before Ramos, the last player to hit a hat-trick on his first World Cup start went on to become the tournament's 16-goal all-time record scorer: Germany's Miroslav Klose.

The Morocco game will take place on Saturday, so the imperative for Portugal is to move on as quickly as possible and prepare for that tussle.

"We're going to celebrate, but calm spirits, respecting the Moroccan team," Leao said. "Now it's time to prepare for that game and for sure we'll come in strong."

Leao has showed outstanding form for Milan in Serie A across the last 18 months, but such are the resources available to Santos he is not a certain starter for his country.

There will be games when the coach prefers other options, but Leao has a long-term future in the team.

"Even though I'm not the first option, when I come on I try to help the team," Leao said. "I have to respect the coach's decisions."

President Rebelo de Sousa told television broadcaster RTP3 it had been one of Portugal's finest nights.

There have been others that have topped it, notably their Euro 2016 title triumph, and there might yet be better days ahead in Qatar.

"I think the selector's choices in general worked well," said Rebelo de Sousa. "The team played well in the first half and also in the second half. The substitutions happened naturally and we still had more goals.

"It was one of the best nights in Portuguese football."