Patrick Herrmann scored twice Sunday as Borussia Moenchengladbach sent Bayer Leverkusen crashing to a humiliating 6-3 home defeat in the German Bundesliga while VfB Stuttgart went down to Borussia Dortmund, dpa reported.
Leverkusen may have managed a fourth-place finish last season but looked distinctly ordinary at the BayArena as Jupp Heynkes' side conceded six goals in a home league match for the first time in the club's history.
After a tentative opening, Moenchengladbach went in front on 20 minutes through Herrmann courtesy of the home side's first serious lapse of concentration.
Leverkusen midfielder Arturo Vidal lost possession cheaply to Mohamadou Idrissou, who powered into the area before crossing the ball for Herrmann to tap home from close range.
Leverkusen drew level through an Eren Derdiyok header four minutes later but Roel Brouwers restored Moenchengladbach's lead on 40 minutes after goalkeeper Rene Adler failed to hold a Thorben Marx shot.
Hermann netted his second of the game shortly before half-time as Leverkusen failed to clear their lines, and Juan Arango made it 4-1 on 56 minutes with a superbly taken free-kick from the edge of the area.
Vidal pulled one back from the penalty spot before Idrissou restored Moenchengladbach's three goal cushion.
Leverkusen hauled off the ineffectual Michael Ballack at this stage but fell further behind on 69 minutes through a Marco Reus shot although Stefan Kiessling did manage to reduce the deficit to 6-3 with a header 20 minutes from time.
"It's not acceptable to concede six goals," said Leverkusen defender Michal Kadlec. "This is a huge disappointment."
In the day's other game, Stuttgart's defence was also in generous mood against Dortmund and Christian Gross's side paid the price, going down 3-1 at home.
Dortmund were fortunate to go in front after just five minutes when Marcel Schmelzer's cross deflected off Stuttgart defender Khalid Boulahrouz and past goalkeeper Sven Ulreich.
Barrios made it 2-0 for the visitors on 26 minutes before an Ulreich error on 37 allowed Mario Goetze to head into the empty net to make it 3-1.
Cacau pulled one back for Stuttgart midway through the second half but Dortmund held on comfortably to register their first win of the season. Stuttgart, meanwhile, remain without a point after two games.