He's supposedly irked by the fact that Real Madrid haven't moved to renew his contract, despite having three years left to run on his current deal worth in excess of €11 million per year.
While an exit from Spain's capital club would be as astounding as it is unlikely, you can never rule out the possibility. How would Ronaldo fit in at another club then?
Here are tactical options for the only three clubs who could feasibly take him on in the current market, excluding the possibility of a ridiculous move to Russia or money-grabbing venture in Paris, to see what the Portuguese hit man could add to a new team.
Roberto Di Matteo's 4-2-3-1 would accommodate Ronaldo perfectly as he already plays in a similar system with his current club.
You'd be hard pressed to find a single person who wouldn't admit that advanced midfield three is insanely dangerous. For defenders, it gets worse, as the line is interchangeable and almost impossible to track, but Ronaldo would likely stick to his favoured left forward position for much of the game.
Di Matteo wouldn't really have to change anything in his team to allow the Portuguese player into his side. Ashley Cole would function as normal in a left-wing-back role and John Obi Mikel would still be required to provide screen cover.
Moving to his previous club's arch-rivals would be contentious no doubt, but that's not been something Ronaldo has been particularly bothered about over the course of his career.
Roberto Mancini also favours the 4-2-3-1 like his name same Di Matteo, so Ronaldo again would fit in nicely at the Etihad Stadium.
He'd slot in on the left, while David Silva took central position and Samir Nasri shifted to the right. Again, this front three is interchangeable and extremely dynamic in supporting the lone striker, be that Sergio Aguero, Mario Balotelli or Carlos Tevez.
In Mancini's newfound experiment, the 3-5-2, Ronaldo would probably function as a Michu-esque deep-lying forward in order to play to his strengths, as the formation offers no room for true advanced widemen.
Never rule out the romantic nature of football.
A return to the Red Devils, the place where his career took full flight, is surely off the cards, but did anyone ever expect Madrid to pay £80 million for him?
Fitting Ronaldo into the team now would be as difficult as it was beforehand, so it could well signal the increasingly inevitable transition Wayne Rooney is making toward central midfield.
Robin van Persie, of course, is the lone striker, and Antonio Valencia would continue on the right with Shinji Kagawa in the No. 10 role.
As unlikely as it is that Real Madrid cannot come to an agreement with their star man, it's certainly interesting to see how he'd slot into prospective lineups.
Which of the three teams looks most formidable with the addition of this goal machine? If Ronaldo leaves, where would he go?