Borussia Dortmund suffered a shock 3-0 league defeat at Bundesliga strugglers Hamburg on Saturday, just three days before their Champions League last 16 clash away to Zenit St Petersburg.
Jurgen Klopp's Dortmund travel to Russia for Tuesday's first-leg clash, but crashed in Hamburg as new coach Mirko Slomka led the hosts to their first league win since November.
Hamburg are in danger of being relegated from the Bundesliga for the first time in their history and sacked coach Bert van Marwijk last Saturday -- after only 143 days in charge -- in the wake of their 4-2 drubbing at bottom side Eintracht Braunschweig.
His successor Slomka signed a two-year deal on Monday and enjoyed a winning debut as his side broke their eight-match losing streak, including a club record seven league matches.
The 46-year-old Slomka punched the air as left winger Petr Jiracek gave Hamburg the lead three minutes before the break after a superb cross from striker Pierre-Michel Lasogga.
The 22-year-old Lasogga, on loan from Hertha Berlin, then added the second when he darted on to a defence-splitting pass from defensive midfielder Tolgay Arslan on 58 minutes to net the hosts' second.
Turkey midfielder Hakan Calhanoglu then sealed Hamburg's three points when he fired home a 91st-minute free kick.
The result lifts Hamburg up to 16th, but still amongst the bottom three relegation places, while Dortmund stay third.
Bottom side Braunschweig are now three points adrift at the bottom after their 2-1 defeat at ten-man Nuremberg in a match where three penalties were saved.
Nuremberg captain Raphael Schaefer saved penalties in each half, while Braunschweig's Marjan Petkovic also saved a spot-kick from Japan midfielder Hiroshi Kiyotake with 20 minutes to go.
Nuremberg had Sweden centre-back Per Nilsson sent off after just 32 minutes for bringing down Norway's Havard Nielsen, who was through on goal.
Striker Domi Kumbela scored his fourth goal in two games when he put Braunschweig ahead on 34 minutes, but then had his penalty attempt saved by Schaefer.
Hosts Nuremberg equalised, then went ahead in the two minutes after the break as first Kiyotake, then Tomas Pekhart netted.
Nuremberg's goalkeeper Schaefer then saved Braunschweig defender Ermin Bicakcic's penalty attempt, before Kiyotake squandered the chance to put his side 3-1 up.
Borussia Moenchengladbach stay sixth after their 2-2 draw at home to Hoffenheim while Augsburg got back to winning ways with a 4-2 victory at Freiburg to bounce back from last weekend's defeat to Nuremberg, their only loss in the last eight games.
VfB Stuttgart are just above the bottom three after they suffered their seventh straight defeat at home to Hertha Berlin, who ran out 2-1 winners.
Hertha's replacement striker Sandro Wagner headed the winner, three minutes from time, but was then sent off for a second yellow card having only been on the pitch for 12 minutes.
Fourth-placed Schalke, who host Real Madrid in Wednesday's Champions League last 16, first-leg clash, stayed fourth after their goalless draw at home to Mainz 05 on Friday.
European champions Bayern Munich are at Hanover 96 on Sunday evening looking to build on their commanding 16-point lead and extend their record 46-match unbeaten league run.