Borussia Dortmund are unassailable no more in Germany.
The Bundesliga leaders lost for the first time in the league this season, going down 2-1 at Fortuna Dusseldorf on Tuesday.
Paco Alcacer's Bundesliga-record 10th goal of the season from the bench was not enough after Dodi Lukabakio's strike and a stunner from Jean Zimmer condemned the Black and Yellow to defeat.
Lucien Favre's side has played with a renewed verve this season, but they struggled in their attempts to break down Dusseldorf's deep-sitting back line.
With Jadon Sancho, Alcacer, and Achraf Hakimi left on the bench, the visitors found themselves trailing at the break after Lukebakio's 11th goal of the season.
Zimmer's swerving thunderbolt doubled the lead 10 minutes into the second period to put the hosts on the verge of back-to-back wins.
Favre introduced Sancho and Alcacer shortly after that setback and both players were involved as Dortmund cut the deficit nine minutes from time. Sancho played in Lukasz Piszczek down the right and the Polish right-back crossed for Alcacer to nod home. The late revival, however, was ultimately not enough.
The defeat was just the second in 24 games in all competitions this term for Dortmund. They remain six points clear of Borussia Monchengladbach ahead of Friday's clash between the top two, and nine points up on Bayern Munich. The Bavarians, however, can cut that gap to six by beating RB Leipzig on Wednesday.
