Berlin: Bayern Munich's closest challengers, RB Leipzig and Bayer Leverkusen, both lost in the Bundesliga on Saturday to give the eight-time defending champions a chance to move seven points clear at the top.
Second-place Leipzig lost 3-2 against relegation-threatened Mainz and third-place Leverkusen were beaten 1-0 at home against Wolfsburg.
Bayern visit last-place Schalke on Sunday.
"In principle, we don't need to talk about Bayern if we're losing games," Leipzig coach Julian Nagelsmann said of his team's weakened challenge after just one win in four matches. "It's about winning the games yourself."
American midfielder Tyler Adams got his team off to a great start with a goal in the 15th minute, but Moussa Niakhate scored twice for Mainz, either side of Marcel Halstenberg's 30th-minute strike for the visitors.
New signing Danny da Costa set up Leandro Barreiro for Mainz's winner in the 50th.
"It's a difficult starting point but the path is clear," said Mainz coach Bo Svensson, whose team remains second last.
Midfielder Ridle Baku's 35th-minute header was enough for Wolfsburg.
Leverkusen made a good start but Nadiem Amiri and Lucas Alario missed early chances, with Alario striking the post before Wolfsburg gradually settled.
Leverkusen maintained its pressure but the defense took a break and left Baku to head in Renato Steffen's cross against the run of play.
Leverkusen coach Peter Bosz reacted at the break by bringing on former Manchester United defender Timothy Fosu-Mensah for his Bundesliga debut, but Wolfsburg saw out the win.
"We didn't have the strength and freshness at the end," Bosz said.
New blow for Hertha Berlin
Hertha Berlin fans protested against the club's management before the team slumped to another defeat, 4-1 at home to Werder Bremen.
It leaves the ambitious club just two points above Cologne in the relegation zone. Cologne visit Hoffenheim on Sunday.
Hertha had been expected to challenge for European qualification following Lars Windhorst's investment of 374 million euros ($450 million) since June 2019. Only Bayern and Dortmund have spent more on transfers since.
Most of the around 250 fans outside the Olympiastadion called on long-time Hertha general manager Michael Preetz to resign. Hertha president Werner Gegenbauer was also a target, while coach Bruno Labbadia was largely spared criticism as the fans felt he had inherited the problems at the club.
Labbadia's team showed no lack of commitment against Bremen, but fell behind to a penalty from former Hertha striker Davie Selke in the 10th minute.
Matheus Cunha had a chance to equalize with a penalty at the other end in the 21st, but Jiri Pavlenka saved the Brazilian's effort. Omer Toprak scored again for Bremen before Jhon Cordoba pulled one back before the break.
Leonardo Bittencourt made it 3-1 against the run of play early in the second half and American Josh Sargent sealed the efficient visitors' win with a fine strike in the 77th.
Jovic smiling again
Luka Jovic scored his third goal in as many substitute appearances for Eintracht Frankfurt since returning from Real Madrid to seal a 5-1 win at Arminia Bielefeld.
"When you see who we can bring off the bench, that's real quality," Frankfurt defender Martin Hinteregger said. Jovic only managed two goals in 21 league appearances for Madrid after joining from Frankfurt for a reported 60 million euros in 2019.
Augsburg goalkeeper Rafa Gikiewicz saved a penalty to secure a 2-1 win over his former team Union Berlin. Gikiewicz denied Marcus Ingvartsen in the 56th, then produced a fine save to also thwart Taiwo Awoniyi.
Florian Niederlechner, who conceded the spot kick, had already scored twice for the home side.
Freiburg beat Stuttgart 2-1.