It is a time, probably when the financial might of England's Premier League will see the best players there, that neither cules nor Atleti fans want to contemplate, but they will also look back at the brilliance of their teams in this decade and the epic, frenetic encounters between them.
The latest was Tuesday night when Atleti rattled Barca so much that the huge 88,534 Camp Nou crowd dug deep to produce its best atmosphere of the season. Having seen the red and whites win the league in their home two years earlier, Barca fans know that Atletico are the real deal. They understand that pupas tag which stuck with them for so long, the tag of being a team who lost their nerve when they most showed promise, has long gone.
Luis Enrique knows it too – and like the crowd he was pumped up and urging his team on. It made for a glorious spectacle.
Barca know that what Atletico lack in the sublime talents of Luis Suarez, Neymar and the world's best player Lionel Messi, they can attempt to bridge with an obstinate brilliance and spirit which not only comes from the manager, but the many youth products in the team who grew up as Atleti fans.
Atletico are no paupers but, working on a budget a third of Spain’s biggest two, they have to be creative.
Half of Atleti’s outfield players on Tuesday were homegrown. Gabi, Fernando Torres and Koke are Madrid boys who have played for club and country. Saul Niguez has been at the club since 15. Lucas Hernandez, the son of a former Atletico player, was 14 when he joined. They are supplemented by intelligent signings, often from the South American market.
One of their most gifted homegrown heroes has been Torres. On Tuesday, he went from hero to villain in the space of eight minutes. Known as ‘the boy’ because that is what he was when he made his first team debut, he put his side ahead after 25 minutes before receiving a second, needless, yellow card after 33. Until then, Atletico were superior.
It was similar in January when Spain’s best two sides so far this season met at Camp Nou. Then, Koke gave his side the lead before Barca began to work through their gears and dominate. Their task was aided as two defenders, Filipe Luis and Diego Godin, were dismissed. They won 2-1.
On Tuesday, Koke set up Torres, who turned and place the ball through the legs of Marc-Andre ter Stegen. Again, though, Atletico lost a man.
Again, Barça began to dominate and won 2-1, this time thanks to two Luis Suarez goals.
It was the first time that Barca have won seven consecutive games against Atletico in their history, but, once again, there was controversy. Before he scored his 44th and 45th goals of the season, Suarez appeared to lash out at right back Juanfran.
“They protect Barca,” said Filipe Luis of referees. “There is a worry that they’re going to get knocked out. I don’t know what a Barcelona player has to do to get sent off.”
Simeone added: “I can’t say what I want ... I need to think about what I’m saying so I don’t say anything I shouldn’t.”
Barca only need to draw in the second leg next week to reach another semi-final, but Atletico have an away goal and Barca have only kept one clean sheet in 13 European games against Spanish opponents. A 1-0 win will be enough and Atletico have enough to blunt Barca with 11 men.
But getting the result as they did in 2013/14 when they went six games unbeaten against Barca is proving harder. And they can’t afford to lose men – always a possibility with their combative approach.
“I take responsibility for our defeat but now more than ever let’s go to the Calderon for a comeback,” said Torres. “On the personal side I am very sad and feel very responsible. With 11 it would have been different. It’s a complicated situation for me. It’s one of my worst days as a footballer.
“They were two plays which could be a card or not. What’s a shame is that Uefa are more worried about the colours of the shirts and not choosing a referee of the right level.”
Enrique was effusive about his victorious side.
“We must appreciate the difficulty that it is to play against Atletico,” he said. “With this attitude and these players we will go to the end of the world.”
And so will Atletico, as these two greats rivals of these times serve up more enrapturing encounters.
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