Bayer Leverkusen blew their chance to go top of the Bundesliga on Saturday as they lost their 100 percent record with a 2-0 defeat at resurgent Schalke 04.
Defending champions Bayern Munich stay top of the league despite dropping their first points of the season with a 1-1 draw at Freiburg on Tuesday before their dramatic 5-4 win on penalties over Chelsea in Friday's UEFA Super Cup final.
In the battle between the Bundesliga's other two Champions League representatives, Schalke hauled themselves up into midtable and left Leverkusen joint-third behind Bayern and second-placed Dortmund, who are at Eintracht Frankfurt on Sunday.
Both Germany defender Dennis Aogo, who has joined Schalke on loan from Hamburg, and Ghana midfielder Kevin-Prince Boateng, who signed a four-year deal from AC Milan on Friday, started as the Royal Blues picked up their first league win of the season.
Schalke recovered from losing their opening two Bundesliga games against Wolfsburg and Hanover 96 to qualify for the Champions League group stage at the expense of Greek club PAOK on Tuesday and built on that success with what was a convincing home league win against Leverkusen.
Jens Keller's side took the lead with half an hour gone when a free-kick went in off midfielder Marco Hoeger's right shoulder before Peru forward Jefferson Farfan made sure of the win when he drilled home an 83rd-minute penalty after being hauled down in the area.
Earlier Mainz 05 lost their 100 percent record and wasted their chance to go top as they crashed to a 4-1 defeat at Hanover 96.
Mainz took a 12th-minute lead at Hanover through striker Nicolai Mueller, but Thomas Tuchel's side suffered their first defeat after three straight wins as Senegal striker Mame Diouf levelled before Poland forward Artur Sobiech put the hosts in front before the break.
Hanover doubled their lead late on with Ivory Coast forward Didier Ya Konan and midfielder Edgar Prib both scoring in the last 10 minutes for Mirko Slomka's side.
"We started out well and were disciplined, not allowing Hanover any chances," said Tuchel.
"Out of the blue, we conceded an equaliser and it was striking to see the body language.
"The key for us is improving our defending, judging by the way we conceded the first two goals."
Elsewhere, struggling Hamburg picked up their first win of the season after two consecutive defeats with a 4-0 thumping of promoted Eintracht Braunschweig.
Dutch international Rafael van der Vaart put Hamburg ahead in the seventh minute on their first attack before Cameroon striker Jacques Zoua doubled the lead on 17 minutes.
Hamburg confirmed their first three points -- and Braunschweig's fourth straight defeat -- when 19-year-old Turkish midfielder Hakan Calhanoglu came on for Van der Vaart on 79 minutes to claim a brace, including a stunning free-kick.
Meanwhile, Borussia Moenchengladbach moved up to seventh as they romped to a 4-1 home win over Werder Bremen.
Venezuelan winger Juan Arango opened the scoring on 36 minutes with a wonderful strike from the left and Gladbach then added three more in the second half, including one from German international forward Max Kruse.
Norway midfielder Havard Nordtveit's 69th minute own-goal proved to be a mere consolation for Robin Dutt's Bremen, who have now lost two on the bounce.
Wolfsburg enjoyed a 2-0 win at home to Hertha Berlin with Ivica Olic and Diego on target, while Augsburg picked up their second straight win, following up a 2-1 win over VfB Stuttgart last weekend with a 1-0 success at Nuremberg thanks to a late goal from substitute Kevin Vogt.
Stuttgart's defeat last weekend saw coach Bruno Labbadia sacked and so Thomas Schneider will be in charge for Sunday's visit of Hoffenheim.