Two goals from Robert Lewandowski and an Ilkay Gundogan strike were enough to keep Jurgen Klopp's men on course for a successful defence of their title.

Mario Mandzukic made them sweat with a goal which made it 2-1 after an hour, but the home side were unable to equalise and lost Alexander Madlung to a red card in the 84th minute before Lewandowski's second goal sealed Dortmund's win.

Bayern Munich kept alive their title hopes with a hard-fought 2-1 win in a Bavarian derby against Augsburg.

Mario Gomez scored his 24th and 25th goals of the season either side of an equaliser from Ja-Cheol Koo to keep Bayern just three points behind Dortmund.

Vedad Ibisevic scored twice as Stuttgart came back from an early deficit for a comfortable 4-1 victory over Mainz to remain on course for Europe.

Andreas Ivanschitz gave Mainz the lead from the spot after three minutes, but Tamas Hajnal equalised just four minutes later.

Ibisevic scored his first in the 49th minute and Zdravko Kuzmanovic converted a penalty after 65 minutes before Ibisevic struck a second time in the 85th minute.

Cologne and Werder Bremen drew 1-1 with Markus Rosenberg's goal for Bremen in the 24th minute cancelled out by Ammar Jemal in the 39th minute.

Kaiserslautern's hopes of avoiding relegation were dealt a major blow with a 2-1 defeat at home to Hoffenheim.

Sejad Salihovic converted a penalty for Hoffenheim in the 26th minute and Boris Vukcevic made it 2-0 after 71 minutes. Alexander Bugera pulled a goal back for Kaiserslautern in the 86th minute.

Kaiserslautern are marooned at the bottom.

Freiburg fought back from a two-goal deficit to continue their superb run with a 2-2 home draw against Nurnberg.

Nurnberg jumped ahead after eight minutes through Daniel Didavi and the visitors doubled their advantage in first-half stoppage time through Tomas Pekhart.

Daniel Caligiuri pulled a goal back from the spot for Freiburg after 53 minutes and Cedrick Makiadi made it 2-2 in the 79th minute.

In the early evening kick-off, Borussia Monchengladbach drew 0-0 at Hertha Berlin.

The point leaves Monchengladbach nine points clear in fourth but they failed to move level with Schalke in third.

Hertha remain second from bottom, three points from safety.