It's easy to forget, but English soccer was not in a great place 10 years ago. Competitively, at least.
The Premier League was flourishing financially, with the fruits of the league's early business savvy showing up in television deals that were beginning to dwarf any of Europe's other major leagues. But despite a growing financial advantage, England just wasn't producing teams that anyone could reasonably claim were the best in the world.
In both the 2007 and 2008 seasons, three of the four UEFA Champions League semifinalists were English. Liverpool won the whole thing in 2005 -- in a season when they didn't even finish top four in their own league. They made the final again in 2007, and then Manchester United and Chelsea played each other in the final in 2008. But after that, it just sort of stopped.
Over the next nine Champions League tournaments, the Premier League produced just three finalists: twice Manchester United were thoroughly dominated by Barcelona, and then Chelsea won it all in 2012, an occurrence that said almost nothing about the quality of English soccer and everything about the pure randomness often produced by 22 players attempting to kick a bouncy ball into a tiny goal.
Come 2016, the Premier League was the model for how to build a competitive, lucrative and constantly interesting league. But if you were looking for the sport's bleeding edge -- the best players, the most effective ideas, the highest level of execution -- you had to go somewhere else in Europe. And that's ultimately what the Premier League did, too. In 2016, the previous managers of Borussia Dortmund (Jurgen Klopp) and Bayern Munich (Pep Guardiola) competed in their first seasons in English soccer, and the rest is history.
Of the past six Champions League finals, half have been won by English sides, and four featured English runners-up. Since Jurgen Klopp and Pep Guardiola came to England, the Premier League has become the premier league. Klopp's Liverpool and Guardiola's Manchester City dominate Europe, and the two managers' ideas shape the sport.
With Klopp leaving Liverpool at the end of the season, the Sunday match at Anfield could be the final chapter in modern soccer's defining rivalry between two of the greatest coaches ever. The four highest point totals in Premier League history (and six of the top eight) were produced by Klopp and Guardiola teams.
It'll be a long time until we see two teams as good as Liverpool and Man City at the same time again. So, ahead of Sunday's potential title-decider, let's take a look back at how both managers shaped the Premier League -- and each other.