Italy striker Ciro Immobile jumps over Portugal goalkeeper Rui Patricio during their UEFA Nations League match at the San Siro on Saturday in Milan, Italy. Photo: VCG

European champions Portugal became the first team to qualify for the Nations League semifinals on Saturday after holding Italy to a 0-0 draw at the San Siro.

The Portuguese - despite the absence of Cristiano Ronaldo - progressed with one match to play, and are sure to finish top of League A's Group 3, with Italy's hopes in the tournament over.

Poland had already been relegated to League B.

Roberto Mancini's Italians needed a win to keep their hopes of advancing to the final four in June alive but, despite pushing Portugal for over an hour in front of 73,000 spectators at the San Siro, could not find a way through.

Instead, they earned a goalless draw which echoed the stalemate against Sweden a year ago that ended their hopes of reaching the World Cup in Russia.

"It's really satisfying to reach the final phase of this competition," said coach Fernando Santos.

"But it was a very difficult match, above all the first half when I have to admit we had a lot of difficulties."

Portugal host Poland on Tuesday in Guimaraes, in a match that has no significance for either side.

But Santos insisted, "The final match against Poland will be important because it will be in front of our supporters, who are always with us.

"We have to have a great match and to win."

Santos' side had beaten Italy 1-0 in Lisbon and withstood early pressure from the hosts with Lorenzo Insigne and Ciro Immobile both going close in the first half.

Portugal threatened after the break as William Carvalho was denied by Gianluigi Donnarumma and substitute Joao Mario fired over the bar.

"I think we played an excellent match but we didn't manage to score which is an important detail," said Mancini.

"We dominated Portugal and then had a drop in tempo after 70 minutes, which is only to be expected, as we can't play in their half for 90 minutes.

"Even if we're disappointed at not winning, I think we have everything and little by little we're going to also put the attack into place," added Mancini after Italy maintained their record of never having been beaten at the San Siro.

Italy captain Giorgio Chiellini celebrated his 100th Italy cap, exactly 14 years to the day since his debut against Finland.