Bayern Munich's chances of ripping the momentum away from Borussia Dortmund in the Bundesliga title race were massively enhanced with a stunning four-goal first-half blitz in Saturday's crunch Der Klassiker.

The champions started the match two points behind Lucien Favre's men but ran roughshod in a dazzling opening 45 minutes at the Allianz Arena.

Mats Hummels nodded the hosts into a precious early lead before a fellow former Dortmund player, Robert Lewandowski, doubled the advantage, punishing Dan-Axel Zagadou's error in the 17th minute as he clinically tucked away his 200th Bundesliga goal.

Bayern were relentless going forward and their dominance was further rewarded late in the half as Javi Martinez and Serge Gnabry added two more in just over two minutes to send Niko Kovac's men marching towards a pivotal three points.