Bayern routed by leaders VfL Wolsburg

(CNN) -- Bayern Munich suffered a humiliating 5-1 defeat to new leaders VfL Wolsburg which leaves their Bundesliga title defense on the rocks as they slip to fourth place.

Wolfsburg's in-form strikers Edin Dzeko and Brazilian Grafite both scored twice as they assumed leadership in the German title race from Hertha Berlin, who lost 3-1 at home to Borussia Dortmund.

Christian Gentner put the home side ahead in the first half, but Italian World Cup star Luca Toni equalized for Bayern just a minute later.

But Dzeko took the game away from Juergen Klinsmann's men with two second half goals in two minutes, taking his tally to the season to 15.

Strike partner Grafite really rubbed it in with a late double of his own, the second a superb individual effort.

Woflsburg have 51 points from 26 games, heading Hamburg, who beat midwinter 'champions' Hoffenheim 1-0 thanks to a Jonathan Pitroipa goal in the 28th minute, on goal difference.

Hertha are on 49 points with Bayern a further point adrift in a tight championship race.

Dortmund, who moved up to eighth spot with 40 points, went ahead in Berlin's Olympic Stadium with a 26th minute strike from Swiss international Alexander Frei.

Hertha equalized just after the break through Brazilian Raffael, but Dortmund went ahead again through Sebastian Kehl just after the hour. A clinching third by Nelson Valdez wrapped up the three points.

VfB Stuttgart moved up to fifth in the table after their 2-1 win at Bochum.

Friday night's Bundesliga action saw Schalke 04, who recently sacked coach Fred Rutten, beat Arminia Bielefeld 2-0 to go seventh.