Photo: Cristiano Ronaldo Likes IG Post Criticizing Lionel Messi's Ballon d'Or Award

For all intents and purposes, the rivalry between Lionel Messi and Cristiano Ronaldo is effectively over now that they're in the twilight of their playing careers and stationed on different continents.

But the long-running battle hasn't subsided entirely.

Eagle-eyed fans made note of Ronaldo's reaction to an Instagram post questioning the legitimacy of Messi's Ballon d'Or win Monday, his eighth all time.

To be fair, Ronaldo wasn't the only person questioning whether Messi was the most deserving candidate in the Ballon d'Or field.

The 36-year-old helped Argentina win its third World Cup and was the Golden Ball winner in the process. His form in the second half of the season with Paris Saint-Germain was unremarkable, however, and moving to Major League Soccer was a step down in his quality of opposition.

Erling Haaland, who was the best striker in the world en route to helping Manchester City win a treble, was perhaps a more worthy contender.

Of course, it's worth noting that retroactively reducing Messi's Ballon d'Or trophies to five would put him level with Ronaldo. They'd share the record rather than the Inter Miami star sitting alone and setting a mark that will stand for the foreseeable future.

That fact won't have been lost on Ronaldo.

It's doubtful the two icons will ever face off in a competitive fixture again. Maybe fans can at least look forward to years them taking subtle digs at one another, though, to keep the competitive dynamic alive and well.