Albin Ekdal's first goal for Hamburg clinched a 1-0 win against Hertha Berlin that gives their Bundesliga survival hopes a major boost.
Hoffenheim stumbled to a 2-1 defeat at Wolfsburg on Sunday as all six clubs chasing Bayern lost over the weekend.
Bundesliga leaders Bayern Munich saw their winning run come to an end as Schalke battled to a 1-1 draw at the Allianz Arena.
Danny Latza headed a late equaliser as Mainz clinched a 1-1 home draw against Borussia Dortmund in the Bundesliga.
Robert Lewandowski scored an injury-time winner as Bayern Munich snatched a 2-1 win at Freiburg on Friday evening.
Hoffenheim suffered their first Bundesliga defeat of the season as they went down 2-1 at RB Leipzig.