Jurgen Klopp's "Black Yellows" will defend a commanding 4-1 advantage over the reigning Spanish champions, knowing only once has such a deficit been overturned in Champions League history.
But how did Dortmund reach these dizzying heights?
Rewind to 2008, when the Borussian's had just finished in 13th place in the Bundesliga under previous manager Thomas Doll. The German side were in decline while rivals Bayern Munich had just won the German championship, continuing their dominion over German football, having won five of the last 10 Bundesliga titles.
Then in came Jurgen Klopp, who had earlier spent seven years at Mainz 05 and had just resigned following the club's relegation that season. Upon signing a two-year contract with the club, success was immediate, and he guided Dortmund to win the DFB-Supercup, defeating German champions Bayern Munich in the final.
In his first season in charge, the club finished in sixth place in 2009—a modest achievement, yet one that had come on leaps and bounds following their 13th-place berth the season prior.
By 2010, the club had graduated to a fifth-place finish, the first clear signs of progress under Klopp's regime. Thanks to the faith he invested in academy graduates Mario Gotze and Marcel Schmelzer and the run he gave them in his Dortmund side, the Borussians were beginning to look like a force to be reckoned with.
Mats Hummels, who had earlier been brought in on loan from Bayern Munich prior to Klopp's arrival, was quickly handed a permanent stay in a cut-price €4 million deal, and Shinji Kagawa was purchased for €350,000 from Cerezo Osaka. Meanwhile, a certain Robert Lewandowski was snapped up from Lech Poznan for €4.5 million.
Already the signs of a great side were there to be seen.
2010/11 and 2011/12 were to be historic, landmark seasons in the fabric of Dortmund's illustrious history, and back-to-back German championships were won, ending an eight-year wait for the Bundesliga crown.
Fired toward glory by the goals of the red-hot Lewandowski and creative Kagawa, while marshalled at the back by Hummels, the balance of power in German football had shifted, as was evidenced by Dortmund's humiliation of Bayern Munich in May 2012 with a crushing 5-2 victory.
It was one that sent shock waves reverberating through German football and one that suggested Dortmund were here to stay. Though Munich have since regrouped and regained their German crown, there is very little to suggest Dortmund are going away any time soon, save perhaps for the loss of Mario Gotze to their fierce rivals last week, coupled with the uncertain future of Lewandowski.
Yet all those doubts can be placed on hold—for at least one evening. Tonight, history beckons, as does their first Champions League Final appearance since 1997.