Former European champions Hamburg remain in danger of being relegated from the Bundesliga for the first time in their history after losing 3-1 away to Augsburg on Sunday.
They were three goals down inside 42 minutes as Turkey striker Halil Altintop scored a brace and Andre Hahn added another goal for the hosts, and Heiko Westermann's reply just before the interval proved to be a mere consolation for HSV.
Hamburg won the European Cup in 1983 but have not won any major honours since 1987, and now their status as the only club in Germany's top flight never to have been relegated is under serious threat with only two games of the season remaining.
Mirko Slomka's side lie 16th in the table, only a point clear of the automatic relegation places and with a home game against reigning European champions Bayern Munich and a tricky trip to Mainz still to come.
Should Hamburg remain third from bottom, they will earn a reprieve in the form of a two-legged play-off against the side which finishes third in the second tier for the right to play top-flight football next season.
- Defensive concerns for Bayern -
On Saturday, Bayern Munich warmed up for Tuesday's Champions League semi-final second leg at home to Real Madrid with a 5-2 come-from-behind win against Werder Bremen.
Three days after their 1-0 first-leg loss in Madrid, Bayern fell behind twice against Bremen at the Allianz Arena before scoring four second-half goals without reply.
The flattering scoreline failed to mask Bayern's woeful first-half defending, which must sound the alarm bells for coach Pep Guardiola given the danger of conceding an away goal to Real.
Bayern have conceded the first goal in seven of their nine matches since winning the Bundesliga title late last month with a record seven matches to spare.
Once again the Munich defence was left wanting in the first 45 minutes before the reigning European champions roared back.
Bayern blasted Werder 7-0 in Bremen last December, but Czech defender Theodor Gebre Selassie fired the visitors into a 1-0 lead after 10 minutes at the Allianz Arena.
France winger Franck Ribery equalised before Aaron Hunt capitalised on some poor marking for Bremen's second to make it 2-1 at the break.
Bayern equalised again when Thomas Mueller headed on Ribery's corner and Claudio Pizarro was on hand to stab home his shot to make it 2-2 on 54 minutes, then the Peru veteran added his second against his old club four minutes later.
Bastian Schweinsteiger then powered home a header on 61 minutes before Arjen Robben hit the top corner of the net to make it 5-2 on 74 minutes, less than 60 seconds after coming off the bench.
Second-placed Borussia Dortmund held fourth-placed hosts Bayer Leverkusen to a 2-2 draw with all four goals coming in the first 45 minutes.
Goals by Lars Bender and Gonzalo Castro for the hosts were cancelled out by a header from Dortmund's Oliver Kirch and a Marco Reus penalty following a clear handball from Bayer defender Roberto Hilbert.
VfL Wolfsburg's own hopes of Champions League qualification were dealt a blow when they were held to a 2-2 draw at home by Freiburg.
Eintracht Braunschweig remain rooted to the bottom of the table after their 2-0 defeat at Hertha Berlin with USA international John Anthony Brooks and Tunisia striker Sami Allagui scoring the capital club's second-half goals.
Striker Shinji Okazaki became the highest-scoring Japanese player in a single Bundesliga season when he scored his 14th goal to break Shinji Kagawa's previous record in Mainz's 2-0 win at home to Nuremberg.
Okazaki headed his side's opening goal to break Shinja Kagawa's previous record, set for Borussia Dortmund in the 2011/12 season before he joined Manchester United.