Two goals by 19-year-old Patrick Herrmann helped Borussia Monchengladbach beat Bayer Leverkusen for the first time in more than 16 years in a nine-goal thriller at the BayArena that ended 6-3.
Herrmann's opening goal in the 20th minute was cancelled out four minutes later by Eren Derdiyok, but Roel Brouwers and Herrmann gave the visitors a 3-1 half-time lead.
Juan Arango made it 4-1 in the 56th minute and, although Arturo Vidal converted a penalty to trim the deficit two minutes later, Mohamadou Idrissou and Marco Reus had increased the visitors' advantage to 6-2 by the 69th minute.
Stefan Kiessling pulled one back at the other end moments later but that finished off the scoring and there was no way back for the hosts.
Borussia Dortmund bounced back from their defeat to Bayer Leverkusen on the opening day of the season by winning 3-1 at Stuttgart to leave their hosts rooted to the bottom of the Bundesliga.
A Khalid Boulahrouz own goal in the fifth minute sent Dortmund on their way to victory with Lucas Barrios and Mario Gotze giving them a three-goal advantage at half time.
Cacau grabbed a consolation for Stuttgart in the 69th minute, but the Swabians did not deserve more than that as they left the field to a justified chorus of disapproval from their own fans.