Hamburg stunned high-flying Bayer Leverkusen to pick up a rare win and move out of the bottom three of the Bundesliga on Saturday.
Rafael van der Vaart scored the only goal of a fiery encounter midway through the first half to earn Josef Zinnbauer's men only their second win of the season.
Leverkusen were unable to find an equaliser as Hamburg held on for a 1-0 success at the HSV-Arena - and a precious three points in their battle against the drop.
Hakan Calhanoglu, who went on strike in the summer to force his move from Hamburg to Leverkusen through, got an impression of how many friends he had lost in northern Germany when his first touch of the ball was greeted with booing.
There was apparently no love lost between the two sides either, with referee Florian Meyer having his work cut out keeping a lid on things.
His first big decision was to award a penalty for Hamburg when Bernd Leno raced off his line and climbed over Marcell Jansen - a ruling which was made easier by the intervention of his assistant.
Once Leverkusen's protests had been waved away, Van der Vaart stepped up and drilled his penalty right down the middle to give the hosts the lead.
The flow of the game was constantly disrupted as players on both sides refused to hold back in the tackle, leading to numerous scuffles which increased the tension.
Meyer did well to brandish only a few yellow cards before summoning both captains and asking them to spread the message that he would not tolerate any more.
It appeared to work - and as the focus returned to the action Leverkusen attempted to find an equaliser.
Hamburg had their backs to the wall, even though Nicolai Muller nearly doubled their lead on the break.
The biggest chance to level arrived right at the end when Karim Bellarabi raced through and sent his shot wide of Jaroslav Drobny.
The Hamburg goalkeeper may just have got his fingertips to the ball - and that proved enough to turn it onto the far post and out to safety.