World Cup fans employed their lip reading skills and intuition to find out what the 33-yer-old shouted to the referee late in the game to get booked with a yellow.
Although some fans might say that the Portuguese international star deserved a better ending, referee Cesar Ramos apparently thought the only thing he deserved was a yellow card for Ronaldo's protests over a perceived Uruguay foul in second-half injury time.
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World Cup fans took to Twitter to find out who knew best what Ronaldo had said to the referee.
Twitter reactions seem to be wide-ranging: some users suppose that Ronaldo was going to hit the ref, while others think that Portugal's star said he didn't want to bow out of the tournament that early.
The dominating opinion is that it was Ronaldo's foul language that prompted the match official to wave a yellow.
Some users, however, have contended that Ronaldo's been asking for a penalty.