The task facing Kaiserslautern could not be more gargantuan. As they walk out to the monumental backdrop of the Olympiastadion in Berlin on Saturday, they will know they are expected to lose by everyone other than their diehard supporters and, perhaps, secretly, some of them too.

The first 2. Bundesliga side to reach the DFB-Pokal final in more than a decade, they must aim to become the first team to beat Bayer Leverkusen in domestic competition this season. Xabi Alonso’s side are champions of Germany and, before their off night against Atalanta in the Europa League final, had gone a record 51 games without defeat; Kaiserslautern spent much of the campaign trying to avoid relegation to the third tier. They do not so much have a mountain to climb as two Everests stacked on top of one another, teetering ominously.

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It has not always been this way. Until last month, Kaiserslautern had four league titles to Leverkusen’s none. A club with a storied history, having provided five of the starting lineup as West Germany won their first World Cup in the final now immortalised as the Miracle of Bern, Kaiserslautern reached their modern zenith in the 90s, challenging Bayern Munich’s growing hegemony and lifting the Meisterschale in 1991 and 1998. The latter of those triumphs came after they had slingshotted back from a season in the second division, making them the only promoted side to have won the Bundesliga. Spectacular upsets are woven into the fabric of the club, but they will need to do something even more improbable this weekend.

“In football, miracles can happen,” says Thomas Hengen, Kaiserslautern’s CEO, with a smile. Speaking via video link before travelling to Dublin to watch Leverkusen’s first loss in just under a calendar year, he gives off an air of quiet optimism. “I think we have nothing to lose. We can enjoy the game but we will fight, [do] what we can do, with 100% of our quality … it’s the last dance, so to say.”

Hengen took up his role in 2021 with Kaiserslautern in the 3. Liga, an unprecedented low. They were promoted in 2022, but are still a long way from former glories. Despite consistently competing in Europe around the turn of the millennium, reaching the semi-finals of the Uefa Cup in 2001 with a team featuring Youri Djorkaeff and Miroslav Klose, the club ran into severe financial trouble – exacerbated by the expensive renovation of their ground, the Fritz-Walter-Stadion, for the 2006 World Cup – marking the start of a long, drawn-out decline. Since 2006, they have spent only two seasons in the Bundesliga; the last of those ended in 2012, the year after MSV Duisburg, the last second-division team to reach the cup final, were rewarded with a crushing 5-0 defeat by Schalke.

Hengen came through Kaiserslautern’s youth set-up, winning the DFB-Pokal in 1996 before a second spell at the Fritz-Walter-Stadion towards the end of his career, and knows what it means for the club to reach their first cup final since 2003, when they lost to Bayern. “The club means everything for the whole region, it’s not just the city,” he says. “I think over 50-60,000 people will come to [Berlin] and most of them, half of them, will not have any tickets. But they will enjoy the atmosphere in the city, they will celebrate that we have survived in the league and, after 21 years, we are now back in the cup final. They have really hard years behind them. We struggled really in the third division, we fight to survive, we go up … but the people are really 100% loyal and fantastically emotional.”

That emotional investment is not lost on the players, especially after another season of struggle in the league. “It’s going to be crazy, I think; the fans are going to be amazing,” says Ragnar Ache, Kaiserslautern’s top scorer this term. “I don’t know how many fans from Leverkusen are coming but I think that maybe we will have more, that our fans are going to find a way to get more tickets – I don’t know how, but they always find a way – so I really think it’s going to be an amazing experience and an amazing atmosphere.”

Ache played against Leverkusen for Eintracht Frankfurt a few months before Alonso arrived as manager, and has a score to settle. “In the past I played against [Edmond] Tapsoba … I want to get my revenge because that was one of my worst games,” he laughs. Like Hengen, he feels the final being billed as a mismatch for the ages is liberating for him and his teammates. “Everyone is motivated, everyone has a lot of energy and everyone wants to play this game … I’m thinking we cannot lose anything. You are already in the final, you are playing against a team where nobody is expecting you to win, so the only thing you can do is have fun, play your game and, even in the end if you lose, nobody is going to be angry. There is no stress, so you can play freely.”

There is no denying Kaiserslautern were helped to the final by a favourable draw, though they did beat one Bundesliga side, Cologne, in the second round. Having overcome two fellow second-division teams in Nuremberg and Hertha Berlin, they ended another remarkable cup run by defeating Saarbrücken, local rivals in Germany’s south-west and unlikely vanquishers of Bayern, in the semi-finals. They can take encouragement from recent results in the league, having lost one of their last five and thrashed Eintracht Braunschweig 5-0 on the final day. “We’re going to take that confidence into the final now,” says Ache.

The fans are determined to savour a moment of joy after so much suffering. “Now that we’ve managed to stay in the league and know, for example, that we don’t have to play a relegation playoff around the cup final, we’re really looking forward to this game,” says Daniel Widmaier, a member of the BetzeGebabbel podcast, named after the Betzenberg hill on which the Fritz-Walter-Stadion stands.

“For many younger fans, including myself, it’s the biggest game they’ve got to see with their club until today. And considering that the gap in football between the rich clubs like Bayern and Dortmund and the smaller clubs is widening year on year, there is a chance that this will be their last final with Kaiserslautern as well. In this respect, we will all enjoy this game and the atmosphere and will cheer the team on until the last second.”

Although Leverkusen’s defeat in Dublin is another source of hope, it could cut both ways; Alonso’s side may have lost their sheen of invincibility, but they will also be dead set on completing a domestic double after missing out on the treble. For Kaiserslautern, reaching the final is a victory in itself; the revenue from their cup run should help them to improve their squad and aim higher in the league next season. Even so, fans can draw on memories of past miracles and dream of doing the unthinkable. “Imagine Leverkusen losing this final game of the season against the absolute underdogs,” says Widmaier. “This football story would be far too crazy not to find it absolutely marvellous.”