Some moments have the capacity to change the course of history.
Cristiano Ronaldo may not have won the Puskas Award for his awe-inspiring overhead kick against Juventus for Real Madrid in the Champions League quarter-finals last season, but that goal could end up having a far, far bigger impact.
It may just have set in motion the circumstances which see Juve crowned kings of Europe for the third time. That is, of course, if Ronaldo can repeat for Juve what he did with relentless consistency for Madrid for so many years.
The reception that the Portuguese received that night in Turin took him completely by surprise. He is well accustomed to abuse from opposition supporters after netting but the Juventus fans in attendance stood up and applauded.
He loved it, not only for the respect it demonstrated, but for the fact that when he was a young boy growing up in Madeira, he always had a soft spot for the Old Lady.
That would become important when Ronaldo set about making plans to leave Madrid after nine record-breaking seasons.
In addition, while Juventus jumped at the opportunity to sign the five-time Ballon d'Or winner after he’d seen and done it all in England and Spain, they’d been there right at the beginning too.
Juve were one of the first teams to move for the teenage talent Ronaldo when he was making waves in Portugal with Sporting.
He had the chance to move to Turin in 2002 but a late hitch – namely Marcelo Salas’ reluctance to go the other direction – meant Juventus missed out and Ronaldo slipped through their fingers.
That was never going to happen again, once the chance presented itself last year.
Ronaldo’s volleyed goal was most definitely well timed. It not only provoked a reaction that touched the striker. It also came on the same evening that his agent, Jorge Mendes, told sporting director Fabio Paratici that if his client were to leave Madrid, Juve would be his first-choice destination.
Juventus were ultimately eliminated from Europe by Ronaldo’s nerveless last-minute second-leg penalty as the club again suffered at his hands. They are one club, like Atletico Madrid, that Ronaldo seems to haunt in Europe.
The final between Madrid and Juve in Cardiff in 2017 was bitterly disappointing for the Italian side. That year, they honestly thought they had the team to win the trophy outright. But even the best-laid plans can be undone by individual talents like Ronaldo.
Following that win, though, Ronaldo himself was left reeling. It was amid the euphoria of that win in Wales that president Florentino Perez promised the attacker a fresh contract on better terms. It never materialised, much to Ronaldo's bitterness.
After all he’d done for Madrid – with the goals and trophies he accrued – he was powerless as Lionel Messi and Neymar raced clear of him in the best-paid stakes.
Add to that his dismay with Madrid’s hands-off approach when it came to dealing with his tax issues in Spain. He was left alone to face the music, so the word goes, when the club could have stepped in and defended him.
And in the fallout of last year’s meeting in Italy, it all came to a perfect storm. Juve had the chance; if you can’t beat him, sign him.
Paratici knew that for Juventus to recover after their last-eight defeat they were going to need something pretty special. Signing Cristiano Ronaldo is a once-in-a-lifetime kind of event, one that could lift any club to the next level.
It would give everyone connected to Italian football a boost and demand that the rest of the world sit up and take notice.
It would also show that Juventus are serious about winning the Champions League, so they were willing commit to spending €341 million (a €117m transfer fee plus an estimated €224m in wages over the next four years) on the man with five titles and more goals than anybody else.
It’s certainly true that Ronaldo has not caught fire this season in Europe but, then again, Juve have not really impressed as a whole. They were dogged more than brilliant in the group stage and club officials will be hopeful that the team is keeping their best football back for the knockout stages.
Ronaldo – sent off a half hour into his Champions League debut with Juve – has only scored once in Europe so far. But that is in contrast to his devastating form in Serie A, where he is top scorer with 19 goals.
And now he is back to haunt Diego Simeone and Atletico. When you talk about historic hexes, well, Real have got one over their city rivals in Europe, at which you’ll find Ronaldo right at the very centre.
From his penalty which secured la Decima – through his shootout success to win the Undecima – and to his hat-trick in the 2016-17 semi-final, every time Atleti have been blown away on the continental stage, Ronaldo has more often than not been there with his top off celebrating some goal or other.
He will be confident of repeating the trick this week and hoping for more. He claimed two away hat-tricks in the Madrid derby before Atletico moved on from the Vicente Calderon. It was, in many ways, his house by the end.
And what better way to celebrate Atleti’s big house move to the Wanda Metropolitano by knocking them out and returning there for the final, where he could win a sixth Champions League, for a third club.
It might have seemed a remote possibility that night he demolished Juventus with his stupendous overhead kick but every day it becomes a more distinct possibility.