Borussia Dortmund won their eighth consecutive Bundesliga game to take full advantage of defeats for second-placed FC Bayern München and FC Schalke 04 and open up a seven-point lead at the summit.

Polish international Jakub Błaszczykowski opened the scoring for the reigning champions (26) and although Mohamed Zidan equalised (74) for 1. FSV Mainz 05, Shinji Kagawa's eighth goal of the season ensured Dortmund's excellent run continued.

Earlier in the day, Stefan Kiessling and Karim Bellarabi were on target in the final ten minutes to earn Bayer 04 Leverkusen victory against Bayern. That result moved Robin Dutt's side to within four points of Schalke in fourth after the UEFA Europa League contenders suffered a 2-1 defeat at the hands of struggling SC Freiburg. Third-placed VfL Borussia Mönchengladbach travel to 1. FC Nürnberg on Sunday.

Elsewhere, Zdravko Kuzmanović scored twice from the penalty spot in VfB Stuttgart's 4-0 triumph at ten-man Hamburger SV. Hertha BSC Berlin climbed further away from the relegation zone thanks to Nikita Rukavytsya's strike against SV Werder Bremen and Jan-Ingwer Callsen-Bracker's last-gasp penalty earned FC Augsburg a share of the spoils at Hannover 96. VfL Wolfsburg were held to a goalless draw at bottom-of-the-table 1. FC Kaiserslautern in the day's other game.