The Portuguese captain almost single-handedly snuffed out a gallant effort by the home side who went ahead early on.
It was all looking good for Northern Ireland after the men in green went 2-1 up, but then captain Ronaldo stepped up with a hat-trick and it was all over.
The game at Windsor Park was marred by three sendings off – two for Northern Ireland and one for the visitors, along with some typical Belfast rain, but there was no denying the Portuguese wizard had lived up to his billing as one of the best players in the world.
Earlier it seemed Northern Ireland had won the hearts of the scores of Portuguese fans who travelled for the match, many visiting for the first time.
Carlos Silva from the Azores was full of praise as he attended Windsor Park last night on his first trip to Belfast.
"Belfast is a beautiful city, the people are friendly, the music is wonderful, the girls are gorgeous – I love it," he told the Belfast Telegraph.
Here for a flying four-day visit, Carlos is jetting off to the United States today to see Portugal take on Brazil in a friendly in Boston and estimates that he has seen his country play at home and abroad almost 300 times.
Carlos is also a huge fan of Belfast football legend George Best and posed excitedly for photographs in front of the Best mural under the railway bridge outside Windsor Park, but Cristiano Ronaldo was the name on most fans' lips, especially after his one-man show.
The visit of the Portuguese team was also a great treat for the many people from the country who have settled in Northern Ireland.
Americo Ferreira, who is originally from South Africa but lived in Portugal for most of his life before moving to Belfast, brought his two Portuguese-born sons Miguel (13) and Alex (8) to the match.
Americo said: "It's funny for me because I am half and half as I have lived in Northern Ireland for some time.
"The kids are really excited to see Ronaldo, he is a great role model for them, coming from a very poor family and he has worked so hard and now he is the best player in the world."
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