"I didn't expect to score two goals," the Portugal legend admitted after the match.
"I expected one but not two. It was an unbelievable moment."
It certainly was.
Ronaldo bagged a brace as United beat Newcastle 4-1 at Old Trafford.
What an occasion.
There were plenty of memorable moments during the afternoon from start to finish.
Ronaldo being named in the starting line-up, Ronaldo emerging for the first time for the warm-up, Ronaldo walking out for kick-off, Ronaldo’s first goal just before half-time, Bruno Fernandes’ beautiful strike.
However, probably the best moment of the day came in the 62nd-minute.
Newcastle threatened to ruin Ronaldo’s homecoming as Javier Manquillo equalised in the 56th-minute.
However, six minutes later, Ronaldo scored his second goal of the game as he fired through the legs of Freddie Woodman.
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Old Trafford erupted as Ronaldo celebrated with his traditional ’SIUUU’.
Now, though, close-up footage of Ronaldo’s goal and celebration has emerged - and it’s spine-tingling.
After smashing the ball past Woodman, Ronaldo wheels away in front of the camera on the touchline before performing his ’SIUUU’.
But he wasn’t alone.
The footage captures the majority of the 72,732 supporters inside the Theatre of Dreams all shouting ’SIUUU’ in unison as Ronaldo celebrates.
Video: Cristiano Ronaldo celebrates his second goal
It really is magnificent.
We will no doubt see Ronaldo producing his famous celebration plenty more times between now and the end of the season.
But where does Ronaldo’s ‘SIUUU’ celebration come from?
Well, we’ll let him explain.
"I started to say ‘si’, it’s like ‘yes’, when I was in Real Madrid," he said in a 2019 interview.
"When we would win, everyone would say ‘siiiii’ and so I started to say it. I don’t know why, it was natural.
"I was in the USA and we played against Chelsea [in 2013] and I don’t know where this is coming from, the celebration.
"I just scored the goal and it just came out. It was just natural, to be honest. Since that, I started to do it more often and I feel like the supporters and the fans see it and they’re like ‘Cristiano, siiiiiiuuuu’.
"I’m like ‘wow! People are reminded of me because of it!’ So it’s good, and I’ll continue doing it like that."News Now - Sport News