Bayern Munich were held to a 1-1 draw at home by Schalke as the Bundesliga leaders laboured to another unconvincing display on Saturday.
Robert Lewandowski fired Bayern into an early lead with his 15th goal of the season but Naldo equalised from a free kick minutes later and the home side missed a number of chances to claim the winner late on.
The result will increase the pressure on Bayern coach Carlo Ancelotti, who had come in for criticism following a perceived dip in performance over previous games.
However, though Bayern's fourth league draw opened the opportunity for RB Leipzig to close the gap at the top, the newly promoted side failed to take advantage in a 1-0 defeat at Borussia Dortmund.
Pierre-Emerick Aubameyang's 35th-minute goal was enough to give Dortmund all three points as he headed home following a marvellous run down the wing by Ousmane Dembele.
After the hosts spurned a few chances to double their lead, Leipzig thought they had an equaliser with the final kick of the game, but Federico Palacios's goal was rightly ruled out for offside in a close decision.
Bayern's lead atop the Bundesliga grew to four points through 19 games, while Dortmund moved up to third place, 12 points off the leaders and eight behind Leipzig.
But the table is extremely tight behind them, as only two points separate Dortmund and seventh-placed Eintracht Frankfurt after Hoffenheim, Hertha Berlin and Cologne all won earlier on Saturday.
Japan midfielder Genki Haraguchi got Hertha Berlin off to a dream start in the first minute against Ingolstadt, converting Solomon Kalou's cross at the far post, but there was little goalmouth action afterward, as the match ended 1-0.
Hoffenheim bounced back from their first defeat of the season with a 4-0 rout of Mainz.
Mark Uth took Sebastian Rudy's ball on his chest and then blasted it inside the left post to open for Hoffenheim in the fifth minute, but the home side had to wait until the 81st minute for Marco Terrazzino to double the lead and Adam Szalai to complete the scoring with two late goals against his former side.
A late penalty from Anthony Modeste was enough for Cologne to win 1-0 at home and leave Wolfsburg just three points off the relegation zone.
Meanwhile, Lars Stindl struck again, in off the post with just over a quarter-hour remaining, to open the deadlock as Borussia Monchengladbach coach Dieter Hecking celebrated his first win at home with a 3-0 success versus Freiburg.
Stindl had scored twice in the 3-2 win at Bayer Leverkusen the weekend before.
The Monchengladbach captain was involved again when Mahmoud Dahoud crossed for Raffael to seal the win five minutes later, before Patrick Herrmann marked his return from injury by scoring in injury time.