Stuttgart picked up their first win in incredible fashion as they hammered Borussia Monchengladbach 7-0 at home to move up to 13th place.
It took just two minutes for Pavel Pogrebnyak to score and he wrapped up his hat-trick in the 60th minute after another from Georg Niedermeier. Late goals from Zdravko Kuzmanovic, Matthieu Delpierre and Ciprian Marica put the gloss on the scoreline.
Bayern Munich's dreadful start to the season continued as the champions were held 0-0 at home by FC Cologne.
With fans celebrating the start of Oktoberfest, the reigning champions were the dominant team but could not find a way past the Cologne defence. It left Bayern eighth in the league with just five points from four matches, one better off than Cologne. Cologne are also the only Bundesliga club not to have lost against Bayern at Allianz Arena.
Marcel Risse and Andre Schurrle scored within eight minutes in the second half to give Mainz a 2-0 victory at Werder Bremen and top spot in the Bundesliga.
Risse struck in the 53rd minute and substitute Schurrle doubled the lead in the 61st minute as Mainz collected their fourth win in four matches for a perfect 12 points. The win put Mainz top of the table for the first time in club history. Bremen remained on four points for 10th place.
Elsewhere, Wolfsburg finally got their Bundesliga challenge off the ground this afternoon with a welcome 2-0 win at home to Hannover. Second-half goals from Diego and Edin Dzeko earned Steve McClaren's men victory at the fourth time of asking this season.
Kaiserslautern drew 2-2 with TSG Hoffenheim. The visitors took the lead thanks to Luiz Gustavo, but a brace in the second half from Erwin Hoffer put the home side in control. However Gylfi Sigurdsson hit a 77th-minute equaliser.