Borussia Dortmund suffered a shock defeat on home soil, while RB Leipzig thumped Wolfsburg in Saturday's Bundesliga action.
Borussia Dortmund 1-2 Mainz
Dortmund's hopes of finishing second took a knock after losing 2-1 to Mainz at Signal-Iduna Park.
Bote Baku and Yoshinori Mutō put the visitors 2-0 up inside 15 minutes, while Maximilian Philipp netted Dortmund's solitary strike.
RB Leipzig 4-1 Wolfsburg
Ademola Lookman bagged a brace, while Timo Wermer and Jean-Kévin Augustin were also on target as RB Leipzig thumped Wolfsburg 4-1 at the Red Bull Arena.
Werder Bremen 0-0 Bayer Leverkusen
Werder Bremen and Bayer Leverkusen shared the spoils in a goalless draw.
Borussia Monchengladbach 3-1 Freiburg
Gladbach kept their top six hopes alive with a 3-1 win over Frieburg, with Thorgan Hazard, Nico Elvedi and Josip Drmić getting on the scoresheet.
Eintracht Frankfurt 3-0 Hamburg
Eintracht Frankfurt proved too strong for Hamburg as they romped to a 3-0 win at the Commerzbank-Arena.
Marius Wolf, Omar Mascarell and Alexander Meier were all on target for the home side.
Augsburg 1-2 Schalke
A brace from Thilo Kehrer guided Schalke to a 2-1 win over Augsburg to maintain their grip on second place.
Hannover 3-1 Hertha Berlin
Goals from Martin Harnik, Salif Sané and Niclas Füllkrug handed Hannover 3-1 win over Hertha Berlin.
Stuttgart 2-0 Hoffenheim
Mario Gomez netted a brace to lead Stuttgart to a 2-0 victory over Hoffenheim on Saturday afternoon.