The port city club's intrepid approach defied their pre-match place at the foot of the standings, with Pierre-Michel Lasogga's first-half strike condemning the hosts to their fourth league defeat of the campaign.
BVB head coach Jürgen Klopp rewarded Adrian Ramos with a place in the starting line-up following the Colombian's two-goal salvo against RSC Anderlecht in the UEFA Champions League. Lukasz Piszczek and Neven Subotic missed out, however, with FIFA World Cup-winning duo Erik Durm and Mats Hummels returning to the back four in the waylaid duo's stead.
Hamburg were also able to recall Marcell Jansen after a five-week spell on the sidelines, but captain Rafael van der Vaart had to make do with a place on the bench. The visitors nevertheless made the more purposeful start as Nicolai Müller shot wide and Jansen forced a decent near-post save out Roman Weidenfeller before the linesman had time to raise his flag for offside.
Lasogga pokes home
Dortmund were subdued to say the least and on the one occasion they got in behind HSV's disciplined back four, Ramos' first touch evaded him. But if that didn't quite sum up the hosts' first-half efforts, the manner of Hamburg's opener certainly did. Jansen pounced on a mistake by Ramos to release Müller, who combined with Lewis Holtby before unselfishly squaring for Lasogga to stroke home from close range.
BVB upped the ante after the restart with Shinji Kagawa - anonymous during the first half - poking a clever ball into the channel for Kevin Großkreutz, whose clipped cross was cut out by Johan Djourou. Sokratis Papastathopoulos then got up well to direct a Marcel Schmelzer free kick back across the face of goal, but Pierre-Emerick Aubameyang was unable to get his head on it at the far post.
Drobny to the rescue
With the hosts leaving themselves vulnerable to the counter, Hamburg almost doubled their lead with just over an hour on the clock. BVB substitute Milos Jojic gave away a free kick on the right-hand side of the box, with Heiko Westermann meeting Holtby's in-swinging delivery and forcing the best out of Weidenfeller in the Dortmund goal.
Jaroslav Drobny followed suit with some heroics of his own to keep out Ramos and Aubameyang, before Holtby went within a whisker of killing off the contest at the other end after rounding Weidenfeller. BVB ended the game with three forwards on the pitch, but Hamburg held out to record their first Bundesliga win since beating Bayer 04 Leverkusen 2-1 at the start of April.
Line-ups and statistics