Bayern Munich is three points further back ahead of its home game against Leipzig on Wednesday. Substitute Paco Alcacer scored his league-leading 12th goal of the season in the 81th minute for Dortmund, but Duesseldorf held on for its second win in succession - its fourth of the campaign and its first over the league leader for 22 years - to climb out of the relegation zone.
"It's nice that we're the first to beat Dortmund, but it only gives you three points," Duesseldorf coach Friedhelm Funkel said. An injury to Manuel Akanji added to Dortmund's defensive worries ahead of its clash with Gladbach on Friday.
Dortmund captain Marco Reus had an early goal ruled out as Christian Pulisic, making his first league start since Sept. 29, was offside when he was adjudged to have hindered goalkeeper Michael Rensing's sight.
The visitors were caught on a counterattack when Kevin Stoeger lifted the ball over the visiting defense for Lukebakio to shoot inside the left corner in the 22nd. Duesseldorf doubled the lead 10 minutes into the second half, when Zimmer let fly with a shot across goal and inside the far top corner.
Dortmund coach Lucien Favre brought on Jadon Sancho and Alcacer in response. It took 20 minutes for them to make their mark as Alcacer scored his 10th goal as a substitute, but an equalizer never came.
"The team is very young. We're learning every day," said Favre, whose side was already guaranteed top spot going into the league's winter break. "It's a great opening half to the season in any case." GLADBACH CLOSES IN
Moenchengladbach kept the pressure on Dortmund with its 2-0 win over the other promoted side, Nuremberg. Thorgan Hazard atoned for missing a penalty with the opener right after the break and Alassane Plea sealed it late with his ninth goal of the season.
Nuremberg could finish the 16th round bottom if Hannover wins at Freiburg on Wednesday. Gladbach next visits Dortmund on Friday. Also, Augsburg held Hertha Berlin to a 2-2 draw in the capital, and Wolfsburg defeated Stuttgart 2-0 at home to leave the visitors in the relegation zone.
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