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The journey is a short one, and once upon time it was a pleasurable one as well. But not anymore.

From the Santiago Bernabeu to the Vicente Calderon lies a seven-kilometre path, one that's almost entirely downhill. From Real Madrid's home down to Gran Via and then on to the Puerta de Toledo, the descent is gentle. But then as you close in on the Calderon, Calle de Toledo drops more steeply down to the Manzanares, where you turn right to find the home of Atletico Madrid.

It's dated, shabby. It has holes in both sides and hangs over the motorway running alongside the river. But more than anything else, it's hostile.

For Real Madrid, this journey has become torturous. For them, making the final descent has become like a drop into a red-flare-lit, post-apocalyptic pit, where Diego Simeone is a dark-arts king leading 11 faithful zombie lieutenants and 50,000 baying followers in slaying rituals of their prisoners in white.

Too dramatic? Probably, but you get the picture.

Almost three years have passed since Cristiano Ronaldo put Real Madrid ahead of Atletico in the 14th minute of the 2013 Copa del Rey final. At that moment, the men from the Bernabeu were on track to extend their unbeaten run against Atleti even further, to 26 matches across 14 truly ridiculous derby years. Atleti's curse was real. Their inferiority complex was undeniable. Time and again, they'd found ways to not win.

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Until, 14 years later, they did the opposite.

Latching onto Radamel Falcao's pass, Diego Costa smashed a left-footed strike off the inside of the post and into the back of the Real Madrid net via Diego Lopez's outstretched glove. Then, in added time, Koke found the head of Miranda, who with a single act found ecstasy, glory and relief.

The cure.

The derby hasn't been the same since.

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Since that evening at the Bernabeu, these capital rivals have met a remarkable 14 times in all competitions, and Saturday's meeting will make it 15. In those, Real have won on only four occasions—in the league, the number is zero—while Atleti have done so on five. Of course, Real, with the 2014 Champions League final, will argue they won the one that really counts, but even they'll concede this capital battle has turned against them.

Last April, Marca dubbed it "the never-ending derby." For a long time for Real Madrid, it was also a never-ending delight, but now it's never-ending torture. Frustration. Despair.

In 2014-15 alone, Simeone's men were the architects of their hated rivals' demise in three different competitions. At the beginning of the season, they snatched away the Spanish Super Cup; soon after, they dealt Real a setback in the league before landing a hammer blow with a 4-0 thrashing at the Calderon in the second meeting; in between, Atleti added insult by dumping their neighbours out of the Copa del Rey.

In one season, Real visited the Calderon four times. Not only did they not win once, they didn't score once; if you want proof of the pit's the Calderon's new powers, a forward line of Ronaldo, Karim Benzema and Gareth Bale played a combined total of 956 minutes inside it last season and left neutered every time.

This is Simeone's doing. Since his arrival, Atletico Madrid has changed beyond recognition. For so long prior to his arrival, they'd been a mess and their own worst enemies, but Simeone has transformed them. Under him, they're relentless, physical, feisty, organised and intensely disciplined. They can fight. They can scrap. They can play. They can win.

More than anything, though, they believe. Simeone has changed the entire club's mentality and pushed it to recapture an identity he once knew as a player. So influential has he been that he now is Atletico; no club in Europe is built around one man in the way Atletico is built around him.

And don't he and his players love sticking it to Real.

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Against a team that thrives in space, Atleti are better than anyone at closing it down. They congest the midfield, funnel Real's forwards into clusters of defenders, make the game choppy and prey on their neighbours' soft underbelly.

From Atleti's 2-0 victory at the Calderon last January, Real left sucker-punched and bewildered. A month later after the 4-0 humiliation, they left conquered; it was the beginning of the end for that team and for Carlo Ancelotti. Eight months after that, Atleti's overwhelming of Real in the second half of this season's first meeting was the beginning of the end for Rafa Benitez.

Atleti now own this rivalry. The table ahead of Saturday's showdown that has Atleti in second and Real in third reflects that. The fact that Atleti are the capital's most recent league champions reinforces it.

This is not how it used to be.

During those 14 years between 1999 and 2013, Atleti's capacity for surrendering to Real reached the point where the derby, ahead of the times, took on the existence of a Vine—one sight on a perpetual loop.

In June 2003, Atleti, on the season's penultimate weekend, had the opportunity to hand the title to Real Sociedad with victory over Real; they lost, 4-0. In December the same year, they went behind in the first minute; ditto in January 2008 and October 2008.

Atleti would just concede and wilt. Between 2003 and 2009, they conceded goals in the first minute (three times), third minute, fifth minute (twice), sixth minute and eighth minute of contests with Real. They also had a knack for blunders, for giving away penalties, for feeble defending, for being the butter rather than the knife and for flirting with victory but finding every possible way to avoid it.

By 2010, a decade had passed without an Atleti win. At the Bernabeu, a huge banner depicting horror characters and a frightened child in an Atletico shirt read: "Every derby night: your worst nightmare." In 2011, another read, "Wanted: a worthy rival for a decent derby."

Now those fans might wish they hadn't asked.

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For Real Madrid, this flipped-on-its-head derby is becoming problematic. This now goes beyond bragging rights and extends to Real's sense of divine right. Atleti have emerged as a third Spanish power, challenging Real at home and forcing a power shift in the capital that's hurting Real's other battle. The battle.

The one with Barcelona.

Indeed, Spain's second-biggest rivalry is now having an effect on its biggest. Real Madrid are now fighting wars on two fronts, splitting their attention and draining their energy and resources while Barcelona rumble along.

In each of the last two seasons, Atletico have dealt early defeats to Real that have immediately stripped away margin for error from Madrid's more glamorous bunch. In 2013-14, the scoreline was 1-0; in 2014-15, it was 2-1. Real were playing catch-up after both, and then the real blows came.

Two seasons ago, a 2-2 draw at the Calderon halted Real's late momentum ahead of the season's second Clasico. Real lost that Clasico. They never recovered in the league, just as they never did following the day of destruction last February.

"Atletico party, Madrid lost at sea," said AS the day after the latter.

"Carlo can't [live] with Cholo," said Marca.

"That could be the worst 30 minutes Real Madrid have ever played," said Dani Carvajal to reporters.

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Atletico have become Real's tormentors, but in a way that goes beyond the confines of the rivalry. With their strength, solidarity and clarity in purpose, Simeone and Co. are consistently eating away at Real's conviction, exposing flaws and vulnerabilities in their structure to leave awkward questions and sensations hanging around their rivals from up the hill.

Again and again, Atleti have halted their neighbours' progress, weakened them, undermined them. Whereas once Atleti used to be of assistance to Real—"every year we give Real Madrid nine points: the six we lose to them and the three we take off Barcelona," said club president Enrique Cerezo in 2010, via Sid Lowe of the Guardian—now they're something else entirely.

For Real Madrid, it's pretty hard to win a national war if you can't first win the local one.

As such, the Clasicos have taken on an altered feel in recent seasons. On occasions they've still been massive, of course, but they haven't been definitive; Atletico vs. Barcelona has.

In 2014, Simeone's men clinched the title on the season's final day at the Camp Nou. Exactly a year later, Barcelona returned the favour at the Calderon, having kick-started their incredible run against Atleti at home in between. Now this season, the Catalans' pair of 2-1 victories over Atleti stand as the difference between the league's top two.

Behind them both sit a frustrated Real Madrid, one who can't sink their teeth into their battle with Barcelona because they can't win their own city first.

Not long ago, the nightmares belonged to the other side, and a worthy rival was wanted.

That rival is now theirs, and the nightmares are, too.

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