Hamburg heaped the pressure on Hoffenheim coach Markus Gisdol with a 1-0 win at the Rhein-Neckar Stadium, leaving the hosts inside the Bundesliga relegation zone.
Pierre-Michel Lasogga scored the only goal of a game in which both goalkeepers had performed heroics to keep their side on terms. Oliver Baumann was refusing to let Hamburg through with some inspired saves, while Rene Adler was once again insurmountable between the visitors' posts.
More from FoxSports
The hosts were reduced to 10 men midway through the second half when Ermin Bicakcic was given his marching orders for a second yellow card and this enabled the north German side to increase the pressure late on, culminating in Lasogga's tap-in from Sven Schipplock's pass.
Gisdol may have moved level with Ralf Rangnick as Hoffenheim's longest-serving coach with his 85th game but, in view of the result, it could prove to be his last.