The extent to which fans across planet futbol have been spoiled by a decade of otherworldly dominance by Cristiano Ronaldo and Lionel Messi has never been in sharper focus than it has over these last few weeks.

That’s true even if Wednesday’s Champions League group stage match between Ronaldo’s Juventus and Manchester United provided an outlier, with he 33-year-old Ronaldo turning back the clock against his former club, scoring a gem of a goal in the second half:

His celebration afterward seemed to reveal more a hint of defiance. The message, as he lifted his shirt to show off his shredded abdomen, was clear: “Still got it, still the greatest,” he seemed to be saying. And in that moment, on this stage and against this foe, after a technically perfect finish he made look easy as he had so many times before, it was hard to think that he wasn’t.

As superhuman as they often appear, though, the cold hard reality is that Ronaldo’s and Messi’s turn as the undisputed kings of the world’s most popular sport — they might well go down as the two best to ever play it — is going to end at some point, perhaps sooner than we think.

With Messi, 31, currently sidelined with an arm injury, these last few weeks have shown us what a world in which they are not the best two players looks like. Maybe it started in June, when the pair played in what could be their final World Cup, or when Ronaldo joined Juventus in July after nine seasons with Real Madrid. Maybe there was another hint in September, when Luka Modric, Ronaldo’s former Real teammate, broke the duo’s 10-year stranglehold on the FIFA World Player of the Year award. (Between 2008 and 2017, Messi and Ronaldo each won the honor five times.) Then there was last month’s strangely anticlimactic El Clasico between Madrid and Barcelona that, for the first time in 11 years, featured neither icon.

As pretty as his strike was on Wednesday, it wasn’t enough to give his team the win. An Alex Sandro own goal in the dying seconds of normal time handed the visitors all three points after Juan Mata equalized from a perfect free kick in the 89th minute:

The fact is Ronaldo has struggled with Juve, at least by his own towering standards. He had 17 goals across all competitions before Christmas during his final season in Spain. In 292 La Liga matches for Real, he scored a staggering 311 times. Contrast that to his short time in the defensively suffocating Serie A, where CR7 has just seven goals in 11 matches so far. In six of those contests, he’s been held of the scoresheet entirely.

For the neutral fan, it feels like Ronaldo left Real Madrid too soon. Real has clearly missed him desperately. The club sits sixth in La Liga and has scored just 16 goals, almost half as many as league leading Barca. He had his reasons, he said; last week, the Portuguese pinned the blame for his departure squarely on Real president Florentino Perez.

Look, you can respect Ronaldo’s desire to cement his championship-winning credentials by taking on the significant challenge of carrying Juve over the hump in Europe’s top club competition. The Turin titans made the final in 2017 and 2015, losing to Real and Barcelona, respectively, but they haven’t hoisted the Champions League trophy since way back in 1996. At best, it’s a steep climb. A rape allegation in Las Vegas has already sullied his legacy; to what degree, only time (and the outcome of the Las Vegas’s Police Department’s re-opened investigation) will tell. It would certainly seem to make any ballyhooed swan song in the United States-based MLS less likely, at the very least.

Messi will return to the field soon, thankfully. With 17 goals in 17 games before he got hurt, the Argentine has shown that he’s still got plenty left in the tank. But like his great rival, he’ll inevitably slow down as he nears his mid 30s, too. And with all due respect to the likes of Neymar, Kylian Mbappe and Mohamed Salah, there are no clear heirs apparent in sight.

Ronaldo conjured up a vintage performance on Wednesday, but somehow it still feel bittersweet. “Still got it” may have been his message on the night. But with each passing game there’s probably a more appropriate one that applies to Ronaldo and Messi both: Enjoy watching them while you still can.

Doug McIntyre covers soccer for Yahoo Sports. Follow him on Twitter @ByDougMcIntyre.

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