Hamburg climbed up to fourth in the Bundesliga after edging Eintracht Frankfurt at the HSV Arena.
The hosts spurned chance after chance both before and after Mladen Petric bagged the vital goal just before the hour mark.
In the end it proved enough for Hamburg to leapfrog Bayer Leverkusen and remain in touching distance of the league leaders while Frankfurt drop to 12th place.
Martin Jol's side dominated the game from the start but were let down time and again by finishing.
They could have taken the lead after 12 minutes when Bastian Reinhardt's header was saved on the line by Markus Proll, but from there on the hosts failed to test the Eintracht goalkeeper.
Goalscorer Petric was the most culpable, as after 22 minutes he headed the first of a trio of chances wide of the right-hand post.
Eleven minutes later he let fly with a left-footed shot which flew narrowly wide again, before missing a free header from the middle of the area five minutes before the break.
His redemption came in the 59th minute when he put his side ahead. Piotr Trochowski sailed a cross in from the right wing and this time Petric sent his header past Proll from close range.
Their lead should have been doubled 73 minutes in when Reinhardt also headed wide.
As the game neared its end it looked like those misses would prove vital as Martin Fenin was presented with an excellent chance five minutes from time.
But Hamburg stopper Frank Rost made a magnificent save to stop the Czech Republic international before keeping him out from the resulting rebound too.
