Ivo Ilicevic struck for Hamburg as they scrambled a scarcely deserved 1-1 draw from the first leg of their Bundesliga play-off with Karlsruher.
The second-tier outfit were the better side for large parts of Thursday's clash at the Imtech Arena, having taken a fourth-minute lead through Hamburg youth graduate Rouwen Hennings.
Hennings was the 2. Bundesliga's joint-top scorer this term with 17 goals to his name and displayed all his predatory instincts, latching onto a ball in the left channel and clipping an accurate shot across Rene Adler and in via the post.
Karlsruher continued to look superior to their illustrious opponents, who have never been relegated from the Bundesliga, hitting the woodwork twice inside the space of 10 seconds shortly after the break.
Manuel Torres hit the frame of the goal from inside the penalty area, when he perhaps should have done better, before the ball was cleared to Dimitrij Nazarov, who promptly launched a vicious swerving effort that beat Adler all ends up, but cracked the crossbar.
If Karlsruher fans thought their luck was out, that feeling was compounded when Ilicevic struck in the final 20 minutes, playing a neat one-two with Dennis Diekmeier, before clinically slotting under Dirk Orlishausen in the away goal.
Orlishausen was the Karlsruher hero in the final minute of stoppage time, flinging himself to his right to keep Marcelo Diaz's well-struck volley out.
Having preserved their top-flight status on away goals in last season's play-off, Hamburg will need to shake off two years' worth of shoddy form and likely win at the Wildparkstadion, where Karlsruher lost just twice this season, conceding a meagre seven goals.
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