Karim Bellarabi struck with only nine seconds on the clock before setting up Stefan Kießling deep into stoppage time to give Roger Schmidt's charges all three points at the home of the Westphalians.
Quick out of the blocks
Much of the capacity 80,667 crowd inside BVB's famous stadium had not yet taken their seats when the net was already rippling. It was Bellarabi who got the goal, guiding the ball inside Mitchell Langerak's near post after just nine seconds for the fastest strike in German top-flight history.
It was certainly not the start Dortmund had hoped for, and it didn't get that much better for them either. An industrious Leverkusen showed no fear and actually took the game to their hosts. The fact that forward Stefan Kießling was having more touches of the ball than anybody else was indicative of how far up the field they had pitched their tent.
History on Dortmund's side
If Dortmund could take heart from anything at the end of the first 45 minutes, then it could only be that the last two times they had gone in behind at the break in the league, they had managed to turn the games in the second half – against Stuttgart and Wolfsburg on Matchdays 28 and 29 last season.
There was little to suggest that trend would continue when Bellarabi tested Langerak early in the second half. Heung-Min Son then saw a shot blocked as Leverkusen, who finished the 2013/14 campaign in fourth place, opted to push for a second rather than sit on their narrow lead.
Too little, too late
Dortmund had to raise their game, but in spite of all the attacking potential they had on the field, they were unable to deliver the final ball to get one of their attacking trio into a shooting position. By this time, Leverkusen had also regrouped with Stefan Reinartz replacing Simon Rolfes to bolster their defence.
There was nothing negative about Leverkusen's approach, though, as they posed a persistent threat on the counterattack. Dortmund continued to throw bodies forward and Bernd Leno made his most telling intervention to push Matthias Ginter's header wide as the clock ticked down. There was still time for Bellarabi to tee up Kießling with only seconds remaining, the in-form striker picking his spot in the top right-hand corner to seal victory.
Line-ups and statistics
Check out the previous fastest goals in the Bundesliga in this video, courtesy of the Bundesliga's official YouTube channel