For the past few years, fans all over the world have seen the five-time Ballon d'Or winner celebrate with his signiture pose and phrase 'Siiii'.
Ronaldo has since revealed that he first used the celebration during a pre-season game with English Premier League giants Chelsea back in 2013.
"When we all won, they said, 'siiii!'. I started saying it, I don't know why. It came naturally to me.
"I remember the preseason in Los Angeles. We played against Chelsea, I scored a goal and I did this (mimics the celebration).
"People asked me: 'why did you do it?' I don't know. I did it, I turned around, but naturally, because I always say that the best things happen in a natural way."