Will Porto's unlikely Champions League win ever be repeated?

The 2003-04 season seemed unlikely as it was happening. Looking back today, it seems impossible. Arsenal won the Premier League without losing a single match. Werder Bremen won the Bundesliga behind the transcendent play of 30-year-old Ailton. Valencia won its second LaLiga crown in three years. Lyon won its third straight Ligue 1 title in what would eventually become a seven-year streak. And most notably, after beating Deportivo La Coruña in the semis, Jose Mourinho's FC Porto walloped Didier Deschamps' AS Monaco, 3-0, in the Champions League final. And, just for good measure, a few weeks after the club season ended, Greece rode a series of 1-0 wins to an utterly unthinkable European Championship title in 2004e.

In the moment, this was indeed a pretty strange season. Mega-clubs like Real Madrid and Bayern Munich stumbled, and with so many Spanish clubs peaking at the same time, some of the best teams in Europe were stuck playing in the UEFA Cup (precursor to the Europa League). If ever we were going to have an unexpected Champions League winner, it made sense that it would come in 2003-04.

In the 20 years since, it feels like soccer has done everything it possibly could to ensure that such a result never happens again. But with the 20th anniversary of Porto's win passing this week, and this year's Champions League final on Saturday, it's worth looking back on how that wild run unfolded, how good Porto really were, and how the domino effect that followed -- although, really, it had already begun -- forever changed European soccer.

If a new Porto were to come around in 2024-25, a team from outside of Europe's Big Five leagues (or at least outside its ruling class) with boundless energy, exciting young talent and an up-and-coming manager looking at the game in a different way (and happy to tell you all about it), how far could they rise?