Schalke's defeat at Cologne added to another hugely positive weekend for leaders Bayern Munich in the Bundesliga.
Bayern Munich hammered closest challengers Borussia Dortmund 5-1 in the Bundesliga on Sunday after third-place Schalke were convincingly beaten at home by Cologne.
Der Klassiker should have represented Bayern's toughest test of the season to date but Dortmund were disappointing at the Allianz Arena as they lost for the first time under Thomas Tuchel.
Thomas Muller's brace put Bayern on course before Pierre-Emerick Aubameyang gave Dortmund hope prior to the interval, maintaining his record of scoring in every league game so far in 2015-16.
However, Robert Lewandowski continued his own fine goalscoring form with two goals in 12 second-half minutes before another former Dortmund man, Mario Gotze, added further gloss to an impressive display.
Bayern are now seven points clear of Dortmund and eight ahead of Schalke, whose six-match winning run came to an end against in-form Cologne.
Anthony Modeste's impressive goalscoring streak continued as his sixth league strike of the season put the visitors in front at the Veltins Arena before Yannick Gerhardt and Simon Zoller scored inside the final 11 minutes to move Peter Stoger's men fifth.
Karim Bellarabi earned Bayer Leverkusen a 1-1 draw at home to Augsburg following a Bernd Leno blunder 12 minutes in at the BayArena.
Leno - called up to the Germany squad for the first time this week - attempted to clear Jonathan Tah's backpass but ended up diverting it into his own net after the ball bobbled awkwardly.
Nonetheless, Bellarabi levelled six minutes before half-time to keep Augsburg in the bottom three.