The unusual shapes shaved into the Real Madrid superstar's barnet prompted fans to question whether some sort of religious conversion, product placement or just a mere fashion statement lay behind the new cut.
That chatter intensified as the superstar appeared to make a scissor sign with his hand after scoring his first goal in the 2-2 draw, as the picture below shows.
But the conspiracy theories have now been cut short as a pair of hairdresser brothers from Madrid have come forward to explain everything:
"He told us, as he had on many other occasions that he was looking for something different," Jose and Miguel Siero told Spanish newspaper Marca.
"We know him well and we had the idea of shaving a symbol that represents both peace and the calm a warrior experiences after battle. He agreed."
The brothers added that, far from being a prima donna, Ronaldo is actually a very easy client to work.
"He isn't at all fussy," they added. "Cristiano has a great personality and he's very ambitious. He's a winner. He only thinks of himself...
"There's a personality behind every haircut. And he needs a strong image. It suits him.
"He's very ambitious and a perfectionist. We hit on what he was feeling at that time and it was reflected during the match."
It wasn't all plain sailing, however: while the man himself was happy to be guided by Jose and Miguel, his hair itself put up more of a struggle:
"His hair is very curly and you have to treat it carefully," they explained, adding that the star always wears gel to keep it under control.
"He knows that the television cameras follow his every move and he likes to look impeccable."