They have come to embody football in this modern era, almost outgrowing their clubs and countries to be whole global entities of their own, but within six hours both Lionel Messi and Cristiano Ronaldo have been booted from the 2018 World Cup.
The ramifications of this for both men individually is pretty huge. As Messi and Ronaldo have reached the latter, ever-so-slightly post-peak stages of their career, their shared sole objective has been to outdo the other, and to earn the right to sit one place higher in history's mythical "greatest ever player" leaderboard.
But now, confirmation has almost certainly arrived that neither man will win a World Cup. Ronaldo will be 37 in four years' time and Messi — who has history of prematurely retiring from the Argentina side and is tipped to do so again in the aftermath of this tournament — will be 35.
Neither has scored a goal in the knockout stages of the World Cup in their careers. Messi has played in one final, Ronaldo one semi-final, but this major honour, the medal that was supposed to rule all medals and definitively end the debate once and for all, has eluded the both of them.
They will be crushed by that. But for us, the regular football fan who has just seen the game's two modern greats eliminated three games short of a final, the fun is just getting started.
This has been a thrilling World Cup so far, featuring drama and quality and gripping storylines on a daily basis. Messi and Ronaldo have made their sporadic marks, but this is a World Cup not at all reliant on the superstar pair — and it is better for it.
You can take just today as an example. While Messi grew increasingly despondent as N'Golo Kante thwarted his every move, keeping his contribution only to assists and nothing close to match-defining, Kylian Mbappe was confirming that his name will soon be filling Balon d'Or ballots for a decade or more.
While Ronaldo ran down blind alleys and bewildered only himself with his stepovers against Uruguay, Edinson Cavani and Luis Suarez were combining their incredible work rates with understanding and brilliant technical quality to great effect.
Perhaps the aura has grown too big, that no team — certainly no international team with its limited preparation time and decreased chemistry — can handle the weight of such giants and expect to be able to keep moving forward.
Because aside from the snap moments of individual brilliance, Ronaldo did not make Portugal play better, and Argentina spent its whole tournament desperately trying to find a system that Messi would be happy with and could thrive in, and failed.
This is not going to be a tournament where one player puts his team on his back and carries them to the crown. Neymar has been overshadowed by Philippe Coutinho for Brazil, Harry Kane's goals don't come without the overall excellence of England's attacking movement, and it's almost impossible to pick one single key figure for Spain or Belgium.
The best players at this World Cup — players like Luka Modric, Isco and Juan Quintero — fit into their teams and make them better. Neither Messi or Ronaldo have done that in Russia.
And so the show must go on, with or without its supposed headline acts. Some salivated over a potential Ronaldo v Messi quarter-final battle between Portugal and Argentina, when in truth France against Uruguay really is a much more tantalising game in nearly every way.
None of this is to take away from the ability and careers of these two titans of the game. That their resume doesn't include a World Cup triumph does nothing to detract from their brilliance, and certainly won't end the debates that will befoul social media for years to come.
Even in their swansongs, they gave us something special to remember them by. Ronaldo's free-kick against Spain was unforgettable, and Messi's two touches and finish against Nigeria from another planet.
But this World Cup does not rely upon the greatness of Ronaldo or Messi for its own, and will surely go from strength to strength without them.
New stars will continue rise, and perhaps the next great GOAT debate is about to be spawned from the next two weeks of football.