For the first time in 11 years, Atletico Madrid and Liverpool will do battle in the Champions League with the Spaniards set to host the Premier League champions-elect in the first leg of their last-16 tie.
A lot has changed for both sides since a pair of 1-1 draws in the 2008/09 group stages, when Steven Gerrard’s late penalty at Anfield denied Atletico a place in the knockout rounds.
Atletico have gone from La Liga also-rans to champions of Spain, from occasionally scraping into the Europa League to two-time Champions League finalists.
In the two seasons before Diego Simeone arrived, Atletico finished ninth and seventh. In the seven full seasons since, they’ve never come below third place.
Rafa Benitez’s Liverpool would go on to finish second in the Premier League in 2009 behind an outstanding Manchester United side. Yet in the seasons that followed before Jurgen Klopp’s first full campaign, they’d average a sixth-placed finish – even with Brendan Rodgers’ men finishing as runners-up in 2013/14 to Manchester City.
Klopp’s arrival has transformed Liverpool into the dominant force in English football. The Reds finished second last season with the third-best points tally in Premier League history.
They won the Champions League after finishing as runners-up the season before and this term they have all but sealed their first league title in 30 years and are on course to do so by the greatest margin English football has ever seen.
But there are other factors at play for both clubs. Liverpool’s success has been built on the 'Moneyball' model provided by the Fenway Sports Group owners, most vividly seen in the sale of Philippe Coutinho and subsequent purchases of Virgil van Dijk and Allison.
In Spain, Atletico have taken advantage of a couple of 'off' seasons from Real Madrid and Barcelona, and have developed a knack for identifying South American talent to cement their status as one of La Liga's best.
But undoubtedly the catalysts for both teams’ improvement have been the coaches.
Snarling and fiercely competitive during his playing days, Simeone’s Atletico are the spitting image of their manager and former midfielder.
For decades, Atletico existed in the long shadows cast by Real Madrid and Simeone has played on their status as underdogs to their more glamorous city rivals.
He forged a team that represented the antithesis to Real. Atletico’s squad was built with players willing to fight for every loose ball in every moment of every single match.
Simeone favoured industry and work ethic over flair and individuality. The collective was always more important than any one player’s ego or personal ambition.
Players sacrificed themselves for the system. Antoine Griezmann, at the time one of Europe’s most lethal strikers, could regularly be seen sprinting back to meet an opposition midfielder and prevent a counter-attack.
Simeone inspired devotion from his players and trusted them to carry out his message on the pitch. In turn they swore allegiance to their manager. Atletico’s squad were small and close-knit, like a group of disciples.
“The players would die for Simeone,” former captain Diego Godin said.
“We are with him to the death and also he with us... He marks the way for us and we go with him until the death. That is how you achieve things.”
“I want to thank the mothers of all my players for giving them such big balls,” is how Simeone himself once memorably described it.
At their peak between 2013 and 2017, Atletico were notoriously difficult to beat and score against. They would concede 26 goals in their title-winning campaign of 2013/14 and just five in their final 12 matches of the season.
Two seasons later they’d concede just 18 goals as they finished three points off champions Barcelona. It wasn’t pretty - the most consistent scoreline was 1-0, with the winner typically coming from a set piece – but it was extremely effective.
In the past two seasons, the Simeone cult has been less of a success. Many of his most trusted lieutenants have departed – Godin, Gabi, Filipe Luis, Miranda and Raul Garcia. In the case of Diego Costa, they have gone and returned a faded force.
The replacements have been characterised more by style than steel. Big money has been splashed on the likes of Nicolas Gaitan, Thomas Lemar, Angel Correa and Joao Felix – all great footballers but, crucially, not Simeone players.
More than eight years since taking the reins, Simeone’s message may be starting to wear thin on his squad, just as his compatriot Mauricio Pochettino’s did towards the end of his time at Tottenham.
After the recent 1-0 defeat away at Real, during which home supporters mockingly called for Simeone to stay on, the Atletico coach complained that his side did not carry out his message.
“Lemar came on but didn’t respond in the way I wanted,” the Argentine said of the France international’s involvement as a substitute.
In 2017, the team moved from their former home, the Vicente Calderon cauldron, 12km further outside of the city to the Wanda Metropolitano.
It’s hard to settle in new surroundings and it’s hard to employ the same inferiority complex that was the foundation to Simeone’s success when you play at a shiny, new 68,000-capacity stadium.
The 2019/20 Atletico are a shadow of their former selves. In La Liga they sit 13 points behind the league leaders, Real Madrid. Their Copa del Rey campaign was ended by a shock defeat to Cultural Leonesa.
It was their first exit to lower-league opposition since 2011, when a loss to Albacete spelled the end of Gregorio Manzano’s spell and ushered in the Simeone era.
The Mattress Makers are limping into the Liverpool tie with a spate of injuries to key players and enduring their worst season since Simeone took over.
Simeone may be the second-longest serving manager in Europe’s top five leagues but the evidence is mounting that he is coming to the end of his cycle.
Klopp, meanwhile, took over at Liverpool in October 2015 but is already the eighth-longest serving of coaches in England, Germany, Spain, Italy and France's top leagues.
The German may have only been at Anfield for just over four years, but that represents a dynasty in the modern era. He and Liverpool are on the other end of the cycle, on an upwards trajectory.
Just as Simeone did in Madrid, Klopp has done on Merseyside. He’s won the hearts and minds of his players, who are in awe of their coach – see Jordan Henderson’s emotional speech in the aftermath of the Champions League final.
At the full-time whistle of what is invariably a Liverpool victory, Klopp is seen enveloping each of his players in bear hug after bear hug.
And he’s created just as strong a bond with the supporters. After the bear hugs come the celebratory fist bumps, each greeted by a separate roar from the crowd.
Klopp brought with him from Germany a fast-paced system designed to harry the opposition and launch quickly from defence into attack.
The Gegenpress that brought so much success Borussia Dortmund has been tailored to Liverpool’s needs. By making such fast starts, Klopp’s men often blow opposition sides away by half-time.
Having dropped just two points all Premier League season, the Reds are marching towards the Premier League title and the Champions League holders are favourites to make it two from two in Europe too.
They head into the Atletico tie with expectations at an all-time high at the scene of last season’s final triumph.
Simeone’s side may be a faded force but, forever the underdogs, Atletico will be desperate to play the role of party pooper.
As his time in Madrid looks to be coming to an end, Simeone would love nothing more than conjuring up one last hurrah from his men.
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