Paul Wanner-inspired Heidenheim head to Borussia Dortmund as the league's early pace-setters but face their biggest test so far at the Signal Iduna Park on Friday (kick-off: 8.30pm CEST).

After their 2-0 victory over Eintracht Frankfurt on Matchday 1, Dortmund collected a 0-0 draw at Werder Bremen to head into the international break unbeaten. Since then, the club enjoyed a goal-filled testimonial for Łukasz Piszczek and Jakub Błaszczykowski, while Nuri Şahin got to work with his players who weren't called up for national duty. That includes summer signing Serhou Guirassy, who Şahin confirmed now has no limitations - something he has underlined by naming the Guinea international in the starting XI. Karim Adeyemi and Donyell Malen start on the flanks either side of Julian Brandt, with the Germany international taking the captain's armband as usual skipper Emre Can starts on the bench. In his place comes Felix Nmecha, who is accompanied in the middle of the park by Pascal Groß. In terms of absentees, Gio Reyna will be out for some time after suffering a groin injury with the USMNT. At the back, Nico Schlotterbeck is suspended after collecting a red card against Werder, with Ramy Bensebaini coming into the defence as Şahin names a back four. Yan Couto returns to the bench after missing the Bremen game.

While Dortmund will be happy with their start to the campaign, Heidenheim should be delighted. They have two wins from two and are the surprise league leaders heading into Matchday 3, while also safely navigating a qualifying round of the UEFA Conference League with a pair of victories over Swedish side Häcken. The 2-0 win over St. Pauli on Matchday 1 was an excellent starter before serving up an almost perfect 4-0 victory at home to Augsburg before the pause for international football. Bayern Munich loanee Wanner scored in both games and has proven an early-season revelation, as has the defence which is one of only two teams - the other being Dortmund - yet to concede this season. This has all been much to the delight of head coach Frank Schmidt, who this week said he just wants more of the same. As a result, Schmidt names the same XI that breezed past Die Fuggerstädter before the international break.

Heidenheim's Rise: A Tale of Continuity and Persistence

Heidenheim an der Brenz in southern Germany has not traditionally been on the list of football groundhoppers' away days. It's not that the hilly Ostalb region is unattractive -- far from it. It's more that getting to this community of 50,000 represents a bigger challenge than usual on public transport. And if you come by car, you're well aware on the roads coming in from, say, Stuttgart or Ulm of being very much auf dem Lande (in the countryside).

Heidenheim's remarkable ascent to the Bundesliga for the first time in 2023 has certainly added considerable neutral interest in attending a game at the foot of Hellenstein Mountain, but good luck getting your hands on a ticket for a match at the intimate Voith-Arena with its capacity of just 15,000.

If champions Bayer Leverkusen were die Unbesiegbaren (the unbeatables) last season, Heidenheim became die Unbeugsamen (the unshakables) and kitted themselves out with appropriate words on specially made T-shirts at the end of a maiden top-flight campaign that saw them defy the odds by qualifying for Europe. Gemeinsam unkaputtbar means together indestructible.

For a club that didn't even play 3. Liga football until 2009, how has this rise been possible? Is it down to money? Not particularly. Yes, there is financial support from the Voith machinery company based in the region, but not on the scale that one would associate with the kind of jaw-dropping progress Heidenheim have made.

They pride themselves on two key concepts: kontinuität (continuity) and beharrlichkeit (persistence.) Both qualities are best embodied by Frank Schmidt, coach of the club since 2007 -- yes, 2007! -- and thus the longest-serving manager at any one club in the German professional game.

The immensely likeable Schmidt, born in Heidenheim, where he ended his playing career, personifies the region like no one else. Someday he plans to open a tapas bar with a close friend, but for now his priority continues to be serving the grateful locals with hearty, meaty, substantial football fare.

The Key to Heidenheim's Success: A Steady Hand and a Focused Strategy

Heidenheim keep things simple by signing mostly German players with a smattering of a few Austrians from across the border. Why? So as not to have multiple squad members who need time to adapt to their new surroundings. They also work to a tighter budget than most, and in the absence of a sophisticated international scouting system, knowledge of the local market tops all.

Heidenheim are the early Bundesliga pace setters, but I must confess, I wouldn't have put money on that just a few short weeks ago. This was, after all, a summer of umbruch (radical upheaval.) It was always going to be thus after losing their best three players from last term: Jan-Niklas Beste, Tim Kleindienst and Eren Dinkci.

The club took in around €15 million in fees from the Beste and Kleindienst transfers, but it was perhaps reasonable to doubt whether they could adequately replace them. What they've done, clearly with the dreifachbelastung (burden of competing on three fronts) in mind, is to deepen the squad without breaking the bank. The return of central midfielder Niklas Dorsch, four years after the former Germany youth international left the club, is a coup, while in 18-year-old Paul Wanner, on loan from Bayern Munich, Heidenheim now have one of the most exciting talents in German football playing for them. Naturally left footed, Wanner has excelled so far as playmaker-in-chief.

Then there is the dynamic Brazilian Léo Scienza, an exception to their German/Austrian signing policy but with the important caveat that he has already spent four years in the Bundesrepublik with Schalke, Magdeburg and spectacularly last season with nearby SSV Ulm, the 3. Liga champions for whom he scored 12 times.

Important, too, is that the spine remains intact. Goalkeeper Kevin Müller has been at the club since 2015 and was among the best custodians in the league last time around. Captain Patrick Mainka and defensive midfield specialist Lennard Maloney, a Berlin-born United States international, give stability in front of Müller. Both will be especially highly motivated on Friday's visit to the Westfalenstadion as former Borussia Dortmund players.

Can Heidenheim Maintain Their Momentum Against Dortmund?

It's still fair enough to wonder if Wanner, Adrian Beck and Marvin Pieringer can ultimately be to Heidenheim what Beste and Kleindienst represented in terms of attacking production. So far, though, the portents are positive.

Five competitive matches played in 2024-25 and five wins is a record hard to quibble with. Undoubtedly the scale of the task gets more difficult in the Friday night flutlichtspiel (game under the lights) in Dortmund.

A year ago, also on a Friday night Matchday 3, Heidenheim fell behind 2-0 Dortmund within 15 minutes, only to stay in the game through self-belief and ingenuity, before launching a stirring second-half comeback. The 2-2 result was no fluke but rather a reflection of Heidenheim's willingness to run until the end. They are consistently at the top of the Bundesliga's distance-covered statistics, usually more than 122 kilometres per match.

They grafted for 123 km in the 0-0 draw at home against BVB in February, again a Friday fixture, and might have won the game had it not been for flabby finishing.

It will be fascinating to see if the unlikely Bundesliga leaders can again make it difficult for last season's Champions League runners-up. It would be foolish to opine that they can't.

Dortmund: Kobel - Ryerson, Anton, Süle, Bensebaini - Nmecha, Groß - Malen, Brandt (c), Adeyemi - GuirassySubs: Meyer, Couto, Kabar, Sabitzer, Can, Wätjen, Beier, Duranville, GittensOut: Reyna (groin), Schlotterbeck (suspended)Coach: Nuri ŞahinHeidenheim: Müller - Traoré, Mainka (c), Gimber, Föhrenbach - Maloney, Schöppner - Beck, Wanner, Scienza - PieringerSubs: Eicher, Busch, Siersleben, Kerber, Dorsch, Breunig, Honsak, Kaufmann, ContehOut: Feller (knee), Keller (knee), Niehues (knee), Thomalla (ill)Coach: Frank Schmidt