There is a notion that football is more predictable in the 21st century than ever before. Still, arguably the game’s greatest charm is that each 90-minute match of 11 against 11 is impossible to control, no matter how much is invested in trying to achieve that impossible aim. When that script does get shattered and a team upsets the odds, the rejoicing is these days perhaps even greater.

Eintracht Frankfurt beating Bayern Munich in last season’s DFB-Pokal final was a massive upset, the size of which is best gauged by simply charting the joyous pandemonium that erupted in Frankfurt as Eintracht took the cup home the following day. Over 50,000 fans packed the streets of the city, many of whom waited up to seven hours in Römerberg square for their heroes to take to the balcony of the city hall.

The place swayed and bounced in delight, breaking Bayern’s stranglehold on the German game open a little. Among the festivities, Kevin Prince-Boateng recounted to the crowds a humorous pre-match tactical chat with Ante Rebić: “He told me ‘Brother, hit the ball long!’. I said to him, ‘Brother, I’ll hit the ball long!’” and the phrase instantly took a place in local folklore. Before long, ‘Brother, hit the ball long’ was being printed on t-shirts and an electronica artist even named a track after it.

Axel Hoffmann, an Eintracht fan who blogs about following the club under the name Beve, said: “The frenzy among the fans after the cup win lasted for months. For the young and enthusiastic fans, like the ultras who were founded in 1997 and have defined the terrace scene for Eintracht Frankfurt for over 20 years without the team winning anything, it felt like a great reward for their efforts.”

Bayern were naturally pre-match favourites after winning the Bundesliga by an enormous 21 points while Eintracht had lost four of their final five league matches of the season to limp out of contention for the Europa League qualifying spots.

The underdogs weren’t going to Berlin for the final just for the occasion, though. Their larger-than-life president, Peter Fischer, said to a crowd from a stage a few hours before kick-off, with his voice already hoarse, “I want you all to know we’re going to get our hands on that bleeding cup. I want to be drinking out of the bloody thing tonight. Everyone in the newspaper, everyone you hear on the TV or the radio, every Bundesliga coach, every bookmaker says Eintracht Frankfurt doesn’t have a chance. We’ll show them today we have a bloody chance.”

Hoffmann says that the dramatic end to the cup final is an element that contributed to the outbreak of immense joy in Frankfurt. In a moment seemingly everyone in the city will recall for the rest of their lives, Rebić outsprinted Mats Hummels – after Danny da Costa had hit it long for him over the Germany international – nodded the ball into his own path and stroked it in with his right foot after it had taken two bounces to put the underdogs 2-1 up in the 82nd minute. To the delight of the Eintracht fans, Bayern were denied a clear penalty in stoppage time despite a VAR review, and Mijat Gaćinović made it 3-1 by tapping into an empty net on the break following the Bayern corner that was awarded instead of a spot-kick.

The Eintracht players and backroom staff celebrated wildly. Fischer, a 62-year-old, told a reporter the following day that he had still been in the disco of the club’s hotel in Berlin at 7:30 that morning. Metaphorically, this was pretty much the position the whole club was in over the summer.

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Kevin Prince-Boateng, the heart and soul of the party, had left; the mastermind of the festivities, Niko Kovač, had been wooed away by Bayern; and the immensely popular veteran striker Alex Meier had departed too. A new season was about to dawn and there was a definite risk Eintracht would experience a prolonged hangover.

Adi Hütter was an interesting choice as Kovač’s replacement, and not a man to instantly inspire great optimism. Hoffmann says he was an unknown quantity for Eintracht fans on his arrival. Hütter is not a coach prone to making wild promises or pronouncements, which also avoids the danger that many managers have of getting hemmed in by the expectations or pledges they set. The Frankfurter Rundschau describes Hütter as “courteous, reserved, eloquent and thoughtful.”

Hütter turned out to be the perfect man to keep the party going in Frankfurt, by quietly turning Eintracht’s playing style on its head. Whereas Kovač preferred conservative football, Hütter quickly drilled a high-tempo pressing and attacking style into his team. It only succeeded after the Austrian had the humility to abandon his preferred way of playing four at the back in favour of the three-man defence Kovač had also used, following a poor start to the season that saw a 5-0 defeat at home to Bayern in the German Super Cup and an instant end to their DFB-Pokal defence at fourth-tier Ulm.

A run of 10 wins in 11 matches between September and November set the ambitious tone for the rest of the season. The contrast of style is abundantly clear for anyone to have watched their football, but is neatly shown by comparing their Pokal final win to a 1-1 draw with leaders Dortmund in February.

As glorious as the victory in the final was, there is no disputing it was a smash and grab job with five shots to Bayern’s 19 and 27 percent possession, while the draw with Dortmund saw them go toe-to-toe with the smartest side in the country tactically at that stage of the season, gaining 47 percent possession in one of the sharpest matches played in Germany this season.

Hoffmann speaks of surprise among fans of “how strongly our players have developed and how confidently they have carried on since the cup win.” He cites veteran defensive midfielder Makoto Hasebe, who has taken on the captain’s armband in the absence of David Abraham and made a key contribution to Eintracht’s build-up play. Hütter has compared the Japan international, who is famed for reading Nietzsche and whose philosophical autobiography was a bestseller in his homeland, to a fine wine.

After 24 matches of the current Bundesliga season, the club had already surpassed their goals total from the end of last season. Their front three of Haller, Rebić and Jović have by various yardsticks been among the most dangerous in Europe. While some may suggest that Hütter is fortunate to have such attacking talent at his disposal, it was he who gave them all a chance to flourish by picking them together for the first time against Stuttgart in November; whereas last season, Kovač frequently started just one of the trio.

Twenty-one-year-old Jović’s development this season has been particularly pronounced. After failing to make a breakthrough at Benfica and making just nine starts last season, his 15 goals by the end of February made him the Bundesliga’s top scorer. He has emerged as the technically finest Eintracht player, scoring some particularly delightful goals. These include teeing the ball up for himself from Simon Falette’s cut-back to smash in on volley and win a Europa League tie 2-1 in Marseille in the 89th minute, and a stunning backheel volley from corner sealing a 1-0 win over Schalke in the DFB-Pokal semi-final, topped only by a spinning scissor-kick against Dusseldorf, one of five he hit in a 7-1 win that night.

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Frankfurt have to decide whether to trigger a purchase right when Jović’s loan from Benfica ends this summer, reported to be anywhere between €6m and €12m – a fee they could instantly earn a €30m profit on at the very least.

The credit for that impressive item of business is quite rightly being heaped on the club’s sporting director Fredi Bobic, who Kicker magazine named their Man of the Year in 2018. Germany coach Joachim Löw has described Bobic as “unpretentious, open, confident, clear, strong-willed and focused.”

The first adjective in that comprehensive character description is particularly interesting in highlighting how the former international has set the tone for the zero-fuss approach guiding Frankfurt. Bobic himself is quick to laud the rest of his backroom staff for their part in Eintracht’s current high, with head scout Ben Manga earning plaudits for the skill with which he has identified young and hungry players who have made a big impact despite just seven scouts working for the club. Head analyst Sebastian Zelichowski says that the club have gone in recent years from being outdated to a forerunner in its use of data.

The Commerzbank Arena club aren’t exactly paupers, but they do face the same restrictions as all mid-ranking Bundesliga clubs subject to Germany’s 50+1 rule. Their transfers since Bobic joined in mid-2016 have been defined by shrewdness, with the club’s record signing being the €7m acquisition of Sebastien Haller from Utrecht in 2017 – the kind of fee you might easily see a top-half Championship club paying. The guiding philosophy behind their moves in the transfer market is, like many others in the Bundesliga, to buy talented young players cheaply, develop them and sell at a profit.

While they are yet to see any big windfalls from sales, they have every confidence of gaining some in the next few years. Evan N’Dicka, a teenage centre-back signed from Auxerre for €5.5m in the summer, must now be worth at least three times that fee, while right-back Almamy Touré could be one of the next on the talent development line with the former Golden Boy nominee signed from Monaco for just €750,000.

There remains a healthy degree of flexibility in transfer strategy, with Eintracht in no rush to replace three 30-somethings in midfield despite their interest in young players, and were happy to take on the experienced 26-year-old Austrian defender Martin Hinteregger when given the chance in the January window. Hinteregger is one of five key players in the current Eintracht side there on loan. They also used the loan system to sign Rebić for his first two years, with a bargain €2m purchase option penned in for last summer, along with Filip Kostić who has shone this season on loan following relegation with Hamburg.

Eintracht pride themselves on their cosmopolitism. The club has launched integration projects for local migrants and these values were emphasised with vigour by Fischer when he was re-elected as club president with 99 percent of the vote last year. Fischer pledged to ban anyone who supports the far-right Alternative for Germany party from the club’s membership, saying: “We have members from all backgrounds. Eintracht is made from diversity and internationalism.” Cosmopolitism isn’t a value they just pay lip service to.

They became the only Bundesliga club to field a starting line-up with 11 foreign players in the past two campaigns in a match at Cologne last season. Impressively, those 11 came from as many countries, and their first two substitutes made it 13 players from 13 until Kovač brought a second German player onto the field with a stoppage-time substitution. Hoffmann says the majority of fans have supported Fischer’s clear anti-populist stance: “Since he became president he has embodied passion for Eintracht, and while his unconventional style took some getting used to, his name can now be heard in the stands.”

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Fittingly, Eintracht, thanks to their Pokal win, were given a chance to test themselves against the rest of the continent. They have thrived in the competition so far, winning all six group matches – the first German club to achieve that feat – despite drawing Lazio and Marseille as group opponents. Their fans have relished the chance to take their feel-good spirits around Europe.

A 13,500-ticket allocation for the second leg of their last 16 tie against Internazionale was oversubscribed ahead of sales opening, making for what will be their biggest ever single away following in Europe. Hoffmann says following his team abroad “is just a fantastic experience”.

The only real negative has come off the pitch, with the Eintracht fans annoyed by the decision of German police to raid a stand to search for hidden pyrotechnics (without finding anything) ahead of their second leg of the last 32 at home to Shakhtar Donetsk. Remarkably, the police appear to have acted in response to an interview from Fischer in which the club president promised the “stadium is going to burn” for the tie.

The comments appear to have been made in a jovial way, as Fischer also boasted a couple of breaths later that “no Ukrainian can beat me when it comes to drinking vodka.” One fan was badly injured in the raid after being pushed by a police officer over an advertising board, and Eintracht fans responded by protesting for the interior minister of the local state of Hessen to resign.

Whatever happens in the latter stages of the Europa League and at end of the Bundesliga, it already seems certain to be a season Eintracht Frankfurt fans will cherish. They are not a team used to challenging for honours, having never won the Bundesliga despite being a founding member in 1963. A sixth-place finish in 2012/13 is their best league showing in the past 25 years.

Hoffmann says the club simply can’t compete with the financial muscle of Bayern and Dortmund, nor with commercially funded clubs like Hoffenheim, Wolfsburg and RB Leipzig: “We aren’t going to presume we’ll play regularly in Europe in the coming years.” Eintracht’s current position of fifth in the table makes the Champions League within the realms of possibility for next season, though.

Löw recently said he thinks Eintracht can make it into Europe’s top competition, naming them “among the real top teams in Germany” who are “capable of ripping any defence to shreds.” Time will see just what their potential is, but more importantly, the framework has been put in place that should allow the club to continue to prosper no matter how much transformation is required by selling their most coveted players.

Turning their DFB-Pokal win from what seemed like a joyous climax into just the start of an adventure is an achievement that deserves to be celebrated, wherever that journey takes them.

By Dan Billingham @D_Billingham