Tiny Elversberg chasing Bundesliga promotion 'dream'
Elversberg finished behind Cologne and Hamburg, both of whom won automatic promotion from the second tier, and face Heidenheim, who ended the season third from bottom in the Bundesliga, for a place in the top flight.
Promoted to the second division for the first time two seasons ago, Elversberg are from a town with a population of just 13,000.
If promoted, Elversberg would break the record set by former top-flight side Unterhaching, from a town home to 26,000 residents. Hoffenheim, part of the town of Sinsheim, are the smallest current Bundesliga club, coming from a population of 36,000.
Despite hosting English giants Chelsea in the UEFA Conference League this season, Heidenheim, with a population of 49,000, are also among the smallest clubs in German professional football.
With the combined population of Elversberg and Heidenheim fitting easily into several of the country's larger stadiums, German tabloid Bild nicknamed the playoff 'El Dorfico', or the 'Village Clasico'.
German rail provider Deutsche Bahn got in on the fun, posting on social media on Wednesday that a one-carriage chartered train was organised to transport fans to the match.
Heidenheim hit back with a dig at the national rail company's reliability, telling fans to take a "car or a bus... after all, you want to be there in time for kick-off."
Elversberg's rise has been led by club chairman Frank Holzer, a former player and local businessman who took over in 1990 and has occasionally stepped in as coach.
Holzer is head of a local pharmaceutical company known for making eye drops which has become a major club benefactor.
At press conferences, bottles of eye drops are placed alongside branded soft drinks and refreshments laid out by traditional sponsors.
Coach Horst Steffen said his side should already be proud of what they had achieved.
"The whole story now is already a dream, because it's so unusual," Steffen told reporters.
"If (promotion) happens, I'll be glad. But I don't stay up all night thinking it's not fair we're not in the top flight."
Heidenheim coach Frank Schmidt praised his counterpart on Wednesday, calling Steffen "the coach of the year" and Elversberg "the benchmark of the second division".
Schmidt also tried to tap into the underdog spirit, saying "for us, it's not about stopping relegation, but about achieving something. This is a promotion battle, even if we're the Bundesliga team."
Elversberg will host the return leg on Monday.
Since the Bundesliga playoff was reintroduced at the end of the 2008-09 campaign, the top-flight team has won over two legs in 13 of 16 seasons.